Subject(s)
Analgesia , Brain Chemistry/drug effects , Morphine/pharmacology , gamma-Aminobutyric Acid/physiology , Animals , Drug Interactions , Male , MiceABSTRACT
Effect of zinc sulphate was studied on histamine-induced contractions on guinea-pig ileum. In doses of 1.72 X 10(-7)M or less no effects were observed. Zinc sulphate in doses of 3.44 X 10(-7)M, 6.88 X 10(-7)M and 1.72 X 10(-6)M produced dual effect. Short exposure of tissue for 10 min to zinc sulphate resulted in significant dose dependent potentiation of histamine effect whereas after washing the tissue of zinc sulphate, histamine response was inhibited significantly and in a dose dependent manner. Higher concentrations of zinc sulphate of 3.44 X 10(-6)M and above produced irreversible inhibition of histamine response. The above observations have been explained in terms of zinc-calcium interaction. It is hypothesized that interaction of zinc with calcium may take place extracellularly at membrane level and intracellularly.
Subject(s)
Calcium/pharmacology , Muscle, Smooth/drug effects , Zinc/pharmacology , Animals , Drug Interactions , Female , Guinea Pigs , Histamine/pharmacology , Ileum/drug effects , In Vitro Techniques , Male , Muscle Contraction/drug effectsABSTRACT
A controlled study was conducted on a batch of fifty-four medical students in the paraclinical period of study, to compare the relative effectiveness of self-reading of books, didactic lecture and use of self-instruction kits as teaching-learning experiences. The assessment was done by an immediate and delayed objective type examination as well as questionnaire. The results indicate self-reading to be relatively ineffective. Didactic lectures and use of self-instruction kits have a similar rating in objective assessment while, subjectively, the students expressed a marginal preference for self-instruction kits. Comparison of the performance of the students grouped according to merit reveals that there is no significant difference between the three methods of learning in the lower group while the upper group did perceptibly better with self-instruction kits than with didactic lecture.
Subject(s)
Education, Medical, Undergraduate , Teaching/methods , India , Programmed Instructions as Topic , ReadingSubject(s)
Blood Vessels/metabolism , Endorphins/pharmacology , Enkephalins/pharmacology , Muscle Contraction/drug effects , Muscle, Smooth/drug effects , Prostaglandins E/pharmacology , Animals , Aorta/drug effects , Aorta/metabolism , Chickens , Colon/drug effects , Drug Interactions , Enkephalin, Methionine , In Vitro Techniques , Prostaglandins E/metabolism , Rats , Rectum/drug effects , Stomach/drug effectsABSTRACT
Tetramisole produced a dose-dependent persistent contraction of cat nictitating membrane. This was not significantly altered by prior adrenalectomy or reserpinisation and tyraminisation, but was abolished by prior alpha blockade.
