. The present study was carried out to investigate the changes in plasma fibrinolytic activity, fibrinogen level and platelet count in mongrel dogs and albino rats following myocardial damage. Dogs were subjected to coronary artery ligation to produce myocardial infarction. Myocardial necrosis in albino rats was produced by injecting isoprenaline (85.0 mg/kg s .c . for two days). In dogs as well as in rats myocardial necrosis was confirmed by histological examination of hearts. There was significant diminution of fibrinolytic activity as judged by prolonged euglobulin clotlysis time (ELT) and marked rise in plasma fibrinogen level in both the species of animals where myocardial necrois had set in. In another set of experiments on rats, graded myocardial necrosis was produced by injecting different doses of isoprenaline. Increase in ELT and plasma fibrinogen in these animals corresponded to the grades of necrosis. Suitability of plasma fibrinogen as an indicator of severity of myocardial damage is discussed.

. The effect of bacterial endotoxin (TAB vaccine and Shigella dysenteriae somatic type 0 antigen) and the prostaglandins (PCs) has been studied on the cloacaI temperature of unanaesthetized pigeons. The endotoxin produced hypothermia which showed little dose dependance and which w as more marked after intravenous than after intracerebroventricular injection and a very delayed hyperthermia brought in relief by the circadian rhythm of the body temperature. The PGs E1 E2 F1and F2 were devoid of temperature effect when injected intraventricularly at ambient temperature between 10(-30(C. Injected intravenously, PGE, produced a small hypothermia. Intravenous injection of indomethacin, an inhibitor of PG synthesis, neither affected the normal temperature nor modified the endotoxin hypothermia. It is inferred that PGs are not involved in themoregulation and the early hypothetic effect of the endotoxin may be due to its direct action on the skin blood vessels.

. The value of supplemental zinc in wound healing in nutritionally normal individuals has remained controversial. Possibly, zinc might have differential action on optimally and sub-optimally healing wounds. This hypothesis was experimentally verified by monitoring wound contraction, epithelization in excised wounds (rabbits); tensile strength in healing incision-wounds (guineapigs) and weights of cotton pellet granuloma (rats). Wound/pellet baring animals were divided into control (saline OS ml i.p.) and steroid (dexamethasone 0.17-0.33 mg/kg/day i. m.) groups. Some animals in each group received zinc sulphate topically (1% ointment) or parenterally (25-100 mg/kg i.p.). In control animals with optimal healing zinc sulphate bad no influence. On the other hand, the steroid induced depression of healing was significanlty (P<0.001 to <0.05) prevented by zinc sulphate treatment.

. ST 600 [2-(5 fluoro-O-toluidine)-2 imidazoline hydrochloride] in doses 2.5 to 40 'g injected into the isolated perfused guineapig heart caused an increase in contractile force. The effects of ST 600 were blocked by metiamide (3x 10-5M). Mepyramine or reserpine treatment (5mg/kg i.p.; 24 h prior to the experiment) did not influence the contractile effects of ST 600. Clonidine and ST 600 both produced parallel dose-response curves, which were competitively antagonized by H1-receptor antagonists burimamide and metiamide respectively. It is suggested that the inotropic action of ST 600 is due to stimulation of histamine H2-receptors.

. The effects of histamine, 2-(2-pyridylethylamine) (PEA), a specific H,-agonist and 4methyl-histamine a specific H2- agonist were studied on the isolated aortic strips of guineapig. Histamine and PEA produced dose related contractions of guineapig aortic strips which were inhibited competitively by mepyramine (1 x 10-5M) an H1-receptor antagonist; whereas burimamide the H2-receptor antagonist had no significant effects on the histamine or PEA induced contractions. 4-Methyl histamine failed to produce any significant effect on the guineapig aortic strips. Pretreatment with reserpine (5 mg/kg ip., 24 h before sacrifice) did not produce any significant change in the dose-response curve of histamine. These findings suggest that histamine has direct effects on guineapig aorta and it appears that a predominant distribution of H1-receptor occurs in this tissue.

. In a randomised crossover study on 20 human volunteers, oleandomycin phosphate and triacetyl oleandomycin produced comparable mean serum levels following an oral dose equivalent to 500 mg oleandomycin.The triacetyl ester produced significantly lower level in 4 of the subjects, which could be due to inadequate hydrolysis of the ester in the gut on account of poor esterase activity.

. Histamine (10-80 'g), when injected intracerebroventricularly in conscious mice, was found to induce dose dependent degree of catalepsy. Histamine-induced catalepsy was antagonised by chlorcyclizine, a H1-receptor blocker, while pretreatment with metiamide, a H2-receptor blocker, had no effect on histamine-induced catalepsy. The results indicate that the cataleptic effect of histamine is mediated through activation of H1 receptors.

. Administration of ethanol 2 ml/kg by i.v. drip in normal dogs caused insulin resistance. Studies of plasma inorganic phosphate level proved that there was no defect in phosphate uptake at cellular level. This suggests that anti-insulin effect of ethanol is not mediated through the defective phosphorylation.

. The effect of Sumithion, an organophosphorus insecticide, on reproductive performance of laboratory animals was studied. Adult female rats were taken for studies on reproductive performance and the vaginal smears were examined by maintaining them on basal ration and on 200 ppm dietary level of Sumithion to find out the difference if any, in oestrus cycle. The animals were then mated with males maintained similarly on the experimental ration. Observations were made for pregnancy, gestation, litter size, abortion and compared with controls. Vaginal smear studies did not reveal any change in the regularity of oestrus cycle. Reproduction indices like fertility, gestation. live birth and lactation indices were not affected during these studies at this dietary level of Sumithion. Oestrogenic activity was evaluated by the mouse uterine weight method after administer-ing 40 and 80 mg/kg of Sumithion and compared with stilboesterol. Identical uterine weights of the control and Sumithion treated groups and significant increase in stilboesterol groups indicated that Sumithion at dose levels used is devoid of oestrogenic activity and is unlikely to exert any influence on the sexual behaviour.

. Pretreatment with L-histidine, precursor of histamine, was found to potentiate haloperido1 induced catalepsy and to antagonise methamphetamine stereotypy while pretreatment with chlorcyclizine, a H1-receptor blocker, was found to antagonise haloperidol catalepsy and to potentiate methamphetamine stereotypy: Further, chlorcyclizine was found to antagonise the potentiating effect of L-histidine on haloparidol catalepsy and also the inhibitory effect of L histidine on methamphetamine stereotypy. Our results indicate that the central histaminergic system by exerting a modulatory influence on the striatal dopaminergic system may influence the functioning of the extrapyramidal motor system.

. Toxicity of leaves of K. integra was studied in different animals. The aqueous extract was found to be the most toxic. The 24 how LD50 of the leaf extract was 230 and 560 mg/kg, i.p. in mice and rats, respectively. Since the extract showed delayed toxicity in mice, LD50 based cm 48 and 72 hours mortality data were also calculated.The extract was found to be non-poisonous orally in doses upto 2 g/kg in mice and rats.The toxicity of the extract among the different species of animals was in the following descending order: rabbits>dogs> buffalo calves>mice>rats>sheep. The death in mice, rats, rabbits and sheep was preceded by anoxic convulsions, gasping and coma while the dogs and buffalo calves died in the state of central depression.

. Pretreatment with L-histidine, precursor of histamine, was found to potentiate haloperido1 induced catalepsy and to antagonise methamphetamine stereotypy while pretreatment with chlorcyclizine, a H1-receptor blocker, was found to antagonise haloperidol catalepsy and to potentiate methamphetamine stereotypy: Further, chlorcyclizine was found to antagonise the potentiating effect of L-histidine on haloparidol catalepsy and also the inhibitory effect of L histidine on methamphetamine stereotypy. Our results indicate that the central histaminergic system by exerting a modulatory influence on the striatal dopaminergic system may influence the functioning of the extrapyramidal motor system.