Trifloreted spikelets in species of Anthoxanthum and of Hierochloe are united by the syndrome of two lower male or neuter florets and a differentiated third floret, perfect, bistaminate, and protogynous. Differences in presentation of the floral organs from the third anthoecium separate the genera. Anthers in Anthoxanthum, longer than the f3 anthoecium, keep it open until they migrate on elongating filaments, following behind the protogynous stigma-styles. Both emerge near the apex of the upper glume which tightly encloses all three florets. In Hierochloe the uppermost anthoecium is closed over the androecium and gynoecium until lodicule-controlled anthesis when stigma-styles are exserted unhindered by glumes, and the anthers are exserted later on long filaments from the chasmogamous lower florets. In Hierochloe triandrous lower florets are constant. In Anthoxanthum the two lower florets are neuter in Eurasian species, but in species in Africa, Asia, and Malesia, sometimes f1 florets are also staminate, and very exceptionally both florets present stamens. These reflect a sexual variability in Anthoxanthum unknown in Hierochloe. Data from flowers of 30 species of Hierochloe and 17 species of Anthoxanthum are tabulated; included are ratios of f3 anthers:anthoecium and stigma-styles:the upper glume, G2, two ratios which most reliably reflect the intergeneric floral patterns. Pathways to those varied floral systems are outlined. A sectional taxonomy is proposed for Hierochloe: Sect. Hierochloe autonymum; Sect. nova Monoecia for species in South America where monoecism occurs in all taxa. Andromonoecism is the predominant sexual system in boreal and austral species of Hierochloe, but is interrupted by apomixis in northern Europe.

Hierochloe quebrada, Anthoxanthinae, Aveneae, Poaceae, of steep, tropicalpine granitic ravines in northern Peru is described as new; plants had formerly been referred to H. juncifolia but differ from that southern South American species especially in a shorter lemma with long white ascending marginal hairs, and the lemma of the middle floret with a compound awn inserted mid-point, with a long, brown, twisting colum bearing, inflexed or reflexed, a straw-coloured, straight, equally long arista; the flat leaf-blade is deeply grooved adaxially with simple furrows, and lacks a prominent midrib; ecologically H. quebrada on steep tropicalpine granitic soils to 4600 m is in contrast to H. juncifolia of temperate southern latitudes on volcanic, stony, or sandy soils to about 1750 m. Monoecism is exclusive to all species of Hierochloe in South America; pathways towards its evolution are outlined.

Four species of Hierochloe R.Br. occur in Australia, with the following three of them endemic: H. fraseri Hook.f. in Tasmania, H. submutica F.Muell. restricted to high alpine sites in south-eastern states, and H. rariflora Hook.f. in three eastern states. The fourth, H. redolens (Vahl) Roemer et Schultes, occurs on the eastern mainland and in Tasmania. Three species are regularly andromonoecious, a pattern common to species in both northern and southern hemispheres; however, Tasmanian H. fraseri is an exception in which, in addition to andromonoecism, male sterility in the two lower florets of the spikelet is not uncommon and produces a mixed floral biology. Compared with other departures from andromonoecism, this is a novel condition in the genus, with its genetic control and its reproductive significance unknown.

Two diploid species of Rytidosperma, R. horrens and R. telmaticum, are described from central South Island, the latter as a segregate from R. pumilum. The preferred habitat of R. telmaticum is the margins of kettle-holes, drainage ponds, and other depressions in glacial deposits as one of the dense turf species there; it occurs more sparingly in seral communities on some montane riverbeds, and in one case on sparsely vegetated schist terrain. Rytidosperma horrens is known from only one locality where it grows on the margins of sloping wet flushes. Both species, and their close associates, occupy relatively fertile sites.

Cleistogamy in Festuca of a very simple form with floral expression primarily in anther size; it is a very low frequency phenomenon that occurs almost habitually in F. contracta on several peri-Antarctic islands, and in F. madida of Campbell Island and at high altitudes on the main islands of temperate New Zealand. Facultative cleistogamy occurs in Far East Arctic species, and in F. abyssinica of Africa. Reproduction in Festuca as a whole is centred around self-incompatibility; departures to cleistogamy are very simple evolutionary steps and do not compare for frequency and morphological development with that in the closely related genus Vulpia.

A new generic name Zotovia Edgar et Connor is proposed in tribe Ehrharteae to replace the illegitimate name Petriella Zotov non Curzi. This endemic New Zealand genus is regarded as distinct from Ehrharta, Microlaena, and Tetrarrhena, and comprises three alpine species, Z. acicularis, described as new, and Z. colensoi and Z. thomsonii, both as new combinations. Microlaena is maintained against Ehrharta; its four species, already long established at that rank, are accepted. Lectotypification is proposed for Z. thomsonii, Microlaena carsei, and M. pohmoda.

The biological profile of naratriptan (N-methyl-3-(1-methyl-4-piperidinyl)-1H-indole-5-ethane-sulphonamide), a novel 5HT(1B/1D), receptor agonist, was investigated in a variety of experimental models of relevance to migraine. Naratriptan has high affinity for human recombinant 5HT(1B) and 5HT(1D) receptors (pKi = 8.7 +/- 0.03 and 8.3 +/- 0.1, respectively) and causes contractions of dog isolated basilar and middle cerebral artery (EC50 values of 0.11 and 0.07 mu M, respectively). Naratriptan causes small contractions of human isolated coronary arteries (EC50 value of 0.17 mu M; maximum contraction equivalent to 33% of 5HT maximum). In anaesthetized dogs, naratriptan causes selective vasoconstriction of the carotid arterial bed (CD50 dose = 19 +/- 3 mu g kg(-1)) and, in anaesthetized rats, naratriptan selectively inhibits neurogenic plasma protein extravasation in the dura (ID50 = 4.1 mu g kg(-1)). In a variety of antinociceptive tests, naratriptan has no effect even at high doses. In conscious rats and dogs, naratriptan has high oral bioavailability (71% and 95%, respectively). The data show that naratriptan is a selective agonist at 5HT(1B/1D) receptors, with a pharmacological profile very similar to that of sumatriptan, albeit 2-3 fold more potent. These observations, coupled with high oral bioavailability in animals, suggest that naratriptan has the profile of an orally effective anti-migraine drug.

The in vivo activity of GR205171, a novel, highly potent non-peptide tachykinin NK1 receptor antagonist, has been investigated in the trigeminovascular system in order to assess its potential as an acute therapy for migraine headache. In anaesthetised rabbits, GR205171 attenuated reductions in carotid arterial vascular resistance evoked by the tachykinin NK1 receptor agonist, substance P methyl ester (SPOMe), injected via the lingual artery (DR30 (i.e., the dose producing a dose-ratio of 30) = 0.4 microgram/kg, i.v.). In anaesthetised rats, GR205171 (0.1 and 1 mg/kg, i.v.) produced a dose-dependent inhibition of plasma protein extravasation (PPE) in dura mater, conjunctiva, eyelid and lip in response to electrical stimulation of the trigeminal ganglion. In anaesthetised guinea-pigs, GR205171 (1.10 and 100 micrograms/kg, i.v.) inhibited, by up to approximately 60%, expression of c-fos in the trigeminal nucleus caudalis in response to electrical stimulation of the trigeminal ganglion. It is concluded that GR205171 is a potent antagonist of NK1 receptor-mediated cranial vasodilatation, dural PPE and expression of c-fos in the trigeminal nucleus caudalis. Such a profile of action suggests that GR205171 may have potential as a novel therapeutic agent in the treatment of migraine headache.

GR127935 is the most potent 5-HT1A receptor antagonist yet described, possessing nanomolar affinity at human 5-HT1D receptors. Sumatriptan-induced contractions of the dog isolated basilar artery and saphenous vein are antagonised by GR127935 in an insurmountable manner indicative of its slow dissociation from the 5-HT1D receptor. 5-HT1D receptor-mediated hypothermia and rotational behaviour in guinea-pigs are antagonised potently, and with long duration, by GR127935, administered by a variety of routes. GR127935 also blocks central 5-HT1D autoreceptors in vitro and in vivo. GR127935 has much lower affinity at other 5-HT, and non-5-HT, receptors. In functional studies, GR127935 fails to affect 5-HT2 receptor-mediated 'wet dog shakes' in guinea-pigs and 5-HT1A receptor-mediated inhibition of 5-HT release in rat dorsal raphe nucleus. The compound has a good safety profile in all species tested. It is concluded that GR127935 is a useful pharmacological tool to characterise 5-HT1D receptor function.

The present study has investigated the effects of alpha and beta calcitonin gene-related peptide (CGRP), and the tachykinin neurokinin(1) (NK1) receptor agonist, substance P methyl ester (SPOMe), on carotid vascular resistance, following their injection into the carotid artery bed of the anaesthetized rabbit. The involvement of CGRP and NK1 receptors in nicotine-induced alterations in carotid vascular resistance has also been characterized.alpha-or beta CGRP (1 and 10 pmolkg(-1) i.a.) and SPOMe (0.01 and 0.1 pmolkg(-1) i.a.) caused dose-related increases in carotid arterial blood flow associated with decreases in carotid arterial vascular resistance with little effect on arterial blood pressure. The selective CGRP receptor antagonist, CGRP(8-37) (0.34 mu molkg(-1) i.v.), caused a rightward CGRP displacement of the dose-response curves to both alpha- and beta CGRP; mean dose-ratios, 5 min after antagonist administration, were 14 and 24 respectively. The selective NK1 receptor antagonist, CP99 994 (0.23 mu molkg(-1) i.v.), caused a rightward shift in the dose-response curve to SPOMe; mean dose-ratios, 15 and 75 min after antagonist administration, were 42 and 16 respectively. CGRP(8-37) (0.34 mu molkg(-1)) had no effect on decreases in carotid arterial vascular resistance produced by SPOMe, and CP99 994 (0.23 mu molkg(-1) i.v.) had no effect on vasodilator responses produced by either alpha- or beta CGRP.Intracarotid injection of nicotine (0.002-2 mu molkg(-1)) caused dose-dependent transient, followed by a more prolonged, increase in carotid blood flow and reduction in arterial vascular resistance. The prolonged carotid vasodilator response produced by nicotine (0.2 mu molkg(-1)) was markedly attenuated by CGRP(8-37) (0.34 mu molkg(-1) i.v.) but unaffected by CP99 994 (1.15 mu molkg(-1) i.v.) suggesting a role for CGRP, and not substance P, in this vasodilatation. Neither receptor antagonist affected the transient response produced by nicotine.This study has demonstrated that intracarotid injection of NK1 and CGRP receptor agonists to the anaesthetized rabbit results in an increase in carotid blood flow and a reduction in vascular resistance, indicative of vasodilatation of this artery bed. CGRP mediates the nicotine-induced dilatation of the carotid vascular bed, consistent with its release from sensory nerves. This model should prove useful for the in vivo characterization of NK1 or CGRP receptor agonist and antagonist activities, and in the study of neurogenically induced vasodilatation.

1. The in vitro and in vivo pharmacology of GR203040 ((2S, 3S)-2-methoxy-5-tetrazol-1-yl-benzyl-(2-phenyl-piperidin-3-y l)-amine), a novel, highly potent and selective non-peptide tachykinin NK1 receptor antagonist, was investigated in the present study. 2. GR203040 potently inhibited [3H]-substance P binding to human NK1 receptors expressed in Chinese hamster ovary (CHO) and U373 MG astrocytoma cells, and NK1 receptors in ferret and gerbil cortex (pKi values of 10.3, 10.5, 10.1 and 10.1 respectively). GR203040 had lower affinity at rat NK1 receptors (pKi = 8.6) and little affinity for human NK2 receptors (pKi < 5.0) in CHO cells and NK3 receptors in guinea-pig cortex (pKi < 6.0). With the exception of the histamine H1 receptor (pIC50 = 7.5). GR203040 had little affinity (pIC50 < 6.0) at all non-NK1 receptors and ion channels examined. Furthermore, GR203040 produced only weak inhibition of Na+ currents in SH-SY5Y neuroblastoma and superior cervical ganglion cells (pIC50 values < 4.0). GR203040 produced only weak antagonism of Ca(2+)-evoked contractions of rat isolated portal vein (pKn = 4.1). The enantiomer of GR203040, GR205608 (2R, 3R)-2-methoxy-5-tetrazol-1-yl-benzyl-(2-phenyl-piperidin-3-y l)-amine), had 10,000 fold lower affinity at the human NK1 receptor expressed in CHO cells (pKi = 6.3). 3. In gerbil ex vivo binding experiments, GR203040 produced a dose-dependent inhibition of the binding of [3H]-substance P to cerebral cortical membranes (ED50 = 15 micrograms kg-1 s.c. and 0.42 mg kg-1 p.o.). At 10 micrograms kg-1 s.c., the inhibition of [3H]-substance P binding was maintained for > 6 h. In the rat, GR203040 was less potent (ED50 = 15.4 mg kg-1 s.c.) probably reflecting, at least in part, its lower affinity at the rat NK1 receptor. 4. In guinea-pig isolated ileum and dog isolated middle cerebral and basilar arteries, GR203040 produced a rightward displacement of the concentration-effect curves to substance P methyl ester (SPOMe) with suppression of the maximum agonist response (apparent pKB values of 11.9, 11.2 and 11.1 respectively). 5. In anaesthetized rabbits, GR203040 antagonized reductions in carotid arterial vascular resistance evoked by SPOMe, injected via the lingual artery (DR10 (i.e. the dose producing a dose-ratio of 10) = 1.1 micrograms kg-1, i.v.). At a dose 20 fold greater than its DR10 value (i.e. 22 micrograms kg-1, i.v.), significant antagonism was evident more than 2 h after GR203040 administration. 6. In anaesthetized rats, GR203040 (3 and 10 mg kg-1, i.v.) produced a dose-dependent inhibition of plasma protein extravasation in dura mater, conjunctiva, eyelid and lip in response to electrical stimulation of the trigeminal ganglion. 7. It is concluded that GR203040 is one of the most potent and selective NK1 receptor antagonists yet described, and as such, has considerable potential as a pharmacological tool to characterize the physiological and pathological roles of substance P and NK1 receptors. GR203040 may also have potential as a novel therapeutic agent for the treatment of conditions such as migraine, emesis and pain.

The effects of capsaicin and selective neuropeptide antagonists on pial artery diameter were measured using an on-line image analyser in anaesthetised cats, in order to monitor the effects of mediators released in response to activation of trigeminal nerves.Perivascular injection of CGRP (10(-8) M) and the neurokinin-1 (NK1) receptor agonist substance P methyl ester, SPOMe (10(-6) M) produced an increase in pial artery diameter. The vasodilatory action of these agonists was significantly and selectively inhibited using the CGRP receptor antagonist, CGRP(8-37) (10(-6) M), and the NK1 receptor antagonist, CP99994 (10(-6) M) respectively.Capsaicin (10(-8)-10(-5) M) produced a biphasic response upon perivascular injection that was concentration dependent. At 10(-6) M capsaicin an initial transient vasoconstriction was observed followed by a longer-lasting vasodilatation. The vasodilator component was significantly reduced by CGRP(8-37) (10(-6) M) or CP99994 (10(-6) M).These results show that chemical (capsaicin) activation of trigeminal nerves leads to vasodilatation of feline arteries in situ. This vasodilatation is mediated via the activation of CGRP and NK1 receptors probably via the efferent release of CGRP and a substance P-like peptide.

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Abstract Australopyrum calcis, a self-compatible, triticoid grass of restricted distribution, is described as new; it comprises two subspecies, ssp. calcis, and ssp. optatum; both are associated with limestone. This is the first species of Australopyrum recognised as endemic to New Zealand, and the first endemic diploid (2n = 14) grass found here. The karyotype is the same as in Australian A. pectinatum, and the SAT-chromosome pair is similar to other genera in the tribe Triticeae. Two Australian species are naturalised here, A. retrofractum since mid-19th century, and A. pectinatum, only recently re-collected. Keywords: grass Australopyrum new species A. calcis new subspecies A. calcis ssp. optatum New ZealandTriticeaechromosome numbersnaturalised species

Mrs Jose Steuart first wrote the book “Plants in New Zealand Poisonous to Man” in 1964 as a response to a public health need. That response was continued through to the 1975 edition which I revised, and which was reprinted in 1981. In 1989 Government Printer Books (GP Books) brought out “Poisonous Plants in New Zealand” by Jose Steuart as its replacement and as a revised edition

Migraine headache is thought to be associated with a dilatation of cranial blood vessels, particularly those in the dura mater, and an accompanying localized sterile inflammatory response. Sumatriptan is a highly selective 5-HT1-like receptor agonist which selectively constricts cranial blood vessels (including those in the dura mater). It also inhibits neurogenically-mediated plasma protein extravasation in the dura mater. Haemodynamic studies in anaesthetized animals have shown that sumatriptan selectively constricts the carotid arterial circulation and this effect appears to be restricted to an effect on carotid arteriovenous anastomoses. Sumatriptan has a much more selective pharmacological profile than ergot preparations which are also used in the acute treatment of migraine. The development of sumatriptan has been based on a vascular theory of migraine and its high degree of efficacy in the treatment of migraine strengthens the argument that dilatation of cranial blood vessels is the cause of vascular headache.