PubMed Health⌕ Search

Biomedical subjects

V R Deshpande

Publications and source records attributed to V R Deshpande.

25 records · Page 2Linked to original sources
PubMedDate not supplied

On the mechanism of tachyphylaxis to histamine in guinea pig seminal vesicle.

Repeated administration of high concentrations (10 muglml and above) of histamine produce tachyphylaxis in the seminal vesicle of guinea pig. Acetylcholine partially restores the response to histamine after development of constant tachyphylactic response. No tachyphylaxis occurred (in few experiments) in which the preparation is atropinized. Prior eserinization potentiates the response to histamine. After development of tachyphylaxis to histamine, increasing doses of histamine fail to produce log dose increase in the response. The results suggest that tachyphylaxis to histamine involves, desensitization of the receptors and further, a decrease in the release of acetylcholine may also contribute to the development of tachyphylaxis.

Animals↗
PubMedDate not supplied

Noradrenaline release by nicotinic acid.

In doses (from 100 mug to 1 mg) nicotinic acid produced positive inotropic and chronotropic action on isolated frog heart. This effect was blocked by pronethalol and guanethidine administration. This effect was not observed in reserpinised frogs. Repeated administration of the same dose of nicotinic acid caused development of tachyphylaxis, in frog's heart preparation. The observations indicate that nicotinic acid induced a release of noradrenaline in frog's heart. On other preparations, such as isolated rabbit heart, rabbit's intestine and guinea pig seminal vesicles, nicotinic acid produced a nonspecific direct depressant action.

Animals↗