RESUMO
Histamine reduced sperm viability in a dose- and time-dependent manner, accompanied by rise in intrasperm Ca2+. Further, 2',4'-dichlorobenzamil hydrochloride (DBZ), a Na+-Ca2+ exchange inhibitor, known to elevate intrasperm Ca2+, potentiated both, elevation of intrasperm Ca2+ and spermicidal action of histamine. Pretreatment of sperm with very low doses of H1-receptor antagonists (chlorpheniramine, promethazine or diphenhydramine) prevented the histamine-induced elevation of intrasperm Ca2+ as well as its spermicidal action. However, pretreatment with famotidine, a H2-receptor antagonist did not produce such a protective action. The results strongly suggest that histamine elicits its spermicidal action via H1-receptors present on sperm cells.
Assuntos
Cálcio/metabolismo , Sobrevivência Celular , Clorfeniramina/farmacologia , Difenidramina/farmacologia , Relação Dose-Resposta a Droga , Ejaculação , Histamina/metabolismo , Antagonistas dos Receptores Histamínicos/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Humanos , Masculino , Prometazina/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Fatores de TempoRESUMO
The present investigation was designed to study the spermicidal activity of lidocaine, a membrane stabilizer, and its combination with 2',4'-dichlorobenzamil hydrochloride, a Na+-Ca2+ exchange inhibitor, on human semen and spermatozoa separated from semen. Both drugs per se produced dose- and time-dependent reduction in motility of ejaculated human sperm. Lidocaine was found to potentiate the spermicidal activity of benzamil resulting in significant decrease in time for producing complete loss of ejaculated sperm motility. Sperm revival test revealed irreversible loss of sperm viability indicating a spermicidal rather than spermiostatic action by both the drugs. Furthermore, both benzamil (10-40 mM) per se and benzamil-lidocaine combination (0.5 and 16 mM) produced contraception in rabbit model.
Assuntos
Amilorida/análogos & derivados , Animais , Humanos , Lidocaína/farmacologia , Masculino , Coelhos , Espermicidas/farmacologia , Espermatozoides/efeitos dos fármacosRESUMO
This study was designed to investigate the influence of volatile oil pretreated skin on in vitro permeation from films containing ionized and dodecylamine ion-paired diclofenac sodium (DS). The involvement of skin cholesterol was investigated to determine its possible role in enhancing the permeation of ion-paired DS. Cardamom oil produced the maximum (10 x) in vitro permeation enhancement for ion-paired DS. The carrageenan induced rat paw oedema reduction (up to 12 hr) by cardamom oil was comparable to that of diclofenac injection (s c). Leaching of cholesterol from excised skin in addition to increased partition coefficient following volatile oil skin pretreatment appears to be responsible for in vitro permeation enhancement of DS. Whereas, a mild barrier perturbation effect due to altered cholesterol levels following pretreatment with volatile oils appears to increase the permeation of ion-paired DS across viable skin, thereby producing significant reduction of carrageenan induced paw oedema.