Tolazoline (priscol) an imidazoline. derivative, unlike clonidine, a congener of the same series, produced hypoglycemia when administered by both the intravenous and intracerebroventricular routes in dogs. The drug also lowered the blood sugar levels in rats, increased the deposition of glycogen in the liver and decreased the serum free fatty acid concentrations. The hypoglycemia may be attributed to peripheral utilisation of glucose to glycogen, but a central cholinergic mechanism may also contribute to the same since the centralhypoglycemic effect was blocked by atropine.

The effect of L-dopa, alone and in combination, on brain dopamine, norepinephrine, serotonin, 5-hydroxyindole acetic acid and monoamine oxidase activity was investigated in tremorine induced tremor syndrome in rats. L-dopa, alone and in combination with amantadine, produced a remarkable rise in dopamine and 5-hydroxyindole acetic acid and a reduction in serotonin content.Tremorine failed to influence any of the parameters. The findings suggest that L-dopa and amantadine have pro-found effects on brain biogenic amines which may account for the therapeutic effects as well as behavioural side-effects frequently encountered in clinical practice.

Effect of high doses of tetracycline, chloramphenicol and trimethoprim, for 14 and 21 days was studied on rat blood cholinesterase activity, All the experimental drugs depressed the blood cholinesterase activity and the degree of inhibition was found to be dose and time dependent.

Studies on drug utilisation pattern are often confined to developed countries. However, such studies are required for a healthy medical, pharmaceutical and socio-economic pattern in drug utilisation. The results of a survey on drug usage in a small sample of 812 persons indicate that more health care facilities are required. Though the participants involved in the study were literate, the survey revealed that a high proportion do not have correct concept of drugs and medicaments. vitamins/minerals, supplements and dosage schedules. The study clearly indicates the need for a detailed and large scale survey in different segments of our population.

Rubia cordifolio, Linn.-Indian Manjishtha was studied for the anti-inflammatory effect in rats with carrageenan paw oedema. The plant showed significant anti-inflammatory activity at a dose of 10 and 20 ml/kg of the water extracts. The activity was comparable to that of phenylbutazone (100 mg/kg). No such activity was observed with Rubia tinctorum - the Iranian variety of Manjishtha.

Chlorpromazine (CPZ) inhibited the pinnal reflex in mice in a dose dependent manner. Studies were conducted using agents influencing adrenegric and dopaminergic systems in order to study the mechanism of action. Reserpine, alpha-methyl-p-tyrosine, 6-hydroxydopamine and yohimbine blocked the inhibition of pinnal reflex induced by CPZ. None of the interacting agents had any per se effect on the pinnal reflex. Phenoxy-benzamine, phentolamine and propranolol did not alter the CPZ induced inhibition of pinnal reflex. Imipramine, a rettptake blocker of noradrenaline, did not potentiate the effect of the sub-minimal dose of CPZ. However, sub minimal effect of CPZ on pinnal reflex was potentiated by diethyldithiocarbamate and also by a higher but not by a lower dose of apomorphine. Haloperidol blocked the CPZ induced inhibition of the pinnal reflex. The results suggest that the chlorpromazine-induced inhibition of the pinnal reflex is central in origin and mediated by dopamine at the postsynaptic dopaminergic receptors.

: Alpha-spinasterol, isolaeted from Symplocos spicata, was studied for possible pharmacological actions. The results show that alpha-spinasterol has significant antiinflammatory effect in carrageenin induced acute paw oedema in rats. The antiinflammatory effect is not corticosteroid mediated. Alpha-spinasterol is devoid of any significant CNS activity.

: Metoclopramide, a potent dopamine receptor blocker, elicits typical neuroleptic like effects, and one of these is induction of catalepsy in albino rats. Apart from central dopaminergic and cholinergic mediations in the cataleptic reaction to metoclopramide, the role of other putative neurotransmitters and neuromodulators were investigated. The results suggest that there is involvement of serotonergic system in the cataleptic effect of metoclopramide with possible modulatory role of prostaglandins. Role of histamine as neuromodulator neurotransmitter in this parameter is excluded.

A single injection of cadmium chloride at a dose level of 0.45 mg/kg resulted in consistent testicular necrosis in albino rats as well as in experimentally produced cryptorchid condition, within 72 h by causing injury to vascular endothelium mediated through steady release of catecholamines. The progressive increment of mast cells (MC) running parallel with the intensity of damage of testis following cadmium intoxication as a cryptorchid, was in record. With the prior treatment of reserpice, ergot or removal of adrenal glands, these changes in the mast cells were not observed. On the basis of histological studies it is suggested that testicular lesion or necrosis following cryptorchid condition or cadmium insulation is partly caused by mast cells.

Experiments were conducted in dogs, rats and frogs. Digoxin (100 'g/kg) did not have any significant effect on the myocardial cholinesterase (ChE) activity in the dog and frog. The blood ChE activity was not significantly affected in the dog, but was inhibited in the rat and frog. The in vivo effect of digoxin in the blood ChE activity were confirmed by in vitro experiments. Physostigmine significantly inhibited myocardial and blood ChE activity in these animals. These studies indicate that in contrast to physostigmine, digoxin effect on ChE activity is weak and species-dependent. The artial acetylcholine (ACh) content was significantly raised by digoxin treatment in the dog, rat and frog but the ventricular ACh content was raised only in the dog. The increase in the ACh content due to digoxin treatment could not be correlated to inhibition of ChE activity, and might be due to the increase in the rate of ACh synthesis in the cholinergic neurones. The increase in the ACh content may be one of the factors responsible for the increased cholinergic influence on the heart following digoxin treatment.

A single 4 'g/g injection of 48/80 markedly reduced the gastric tissue histamine concentration in albino rats within 3 h. While gastric tissue histamine concentration was shown to be within normal limits, 18 h after a single dose of 4 'g/g body weight of 48/80, the same was very high 18 after injections of lower doses. A rise in gastric tissue histamine concentration was also observed 18 h after two consecutive, 4 'g/g or lower doses of 48/80 with an interval of 7 h between them. Following three 4 'g/g doses of 48/80 with suitable intervals between them, the gastric tissue histamine concentration was shown to very high even 3 h after the last injection. The findings suggest that following a single standard dose of 48/80 the gastric wall not only become shypo or unresponsive to histamine releasing effect of subsequent doses of 48/80, the later enhances synthesis of histamine in the gastric wall. 48/80 in lower doses also stimulates histamine synthesis in the gastric wall possibly after its initial histamine releasing effect dies down.

The ethyl acetate soluble fraction of alcoholic extract of the bark of Rhamnus procumbens (ERP) showed antinociceptive activity by the rat tail hot wire technique, anticonvulsant effect against supramaximal electroshock seizures and anti-inflammatory property against carrageenin induced pedal oedema in albino rats. Further, ERP did not produce any acute mortality (24 hours) in albino mice after intraperitoneal administration.