Effects of vasopressin and cyclic AMP on water transport at arachnoid villi of cats.
The effects of vasopressin and cyclic AMP on water transport at arachnoid villi into the superior sagittal sinus were examined using the isolated meninges preparations of cats. The meninges preparation, the superior sagittal sinus of which was opened at the midline of the outer surface, was held between two polyethylene tubes. The tubes were fixed vertically in the way that the opened surface of the sinus was directed downward and arachnoid surface upward. Water transport was determined by measuring the tritiated water dripping through the membrane preparation. Vasopressin from less than 50 to 500 muU/ml accelerated the water transport and this effect was dose-dependent. Cyclic AMP from 0.5 to 10 mM was proved to manifest the same effect as vasopressin. This effect of cyclic AMP appeared rapidly in comparison with that of vasopressin, suggesting that the effect of vasopressin may be manifested through cyclic AMP. From these findings a physiological role of vasopressin in cerebrospinal fluid was discussed regarding the regulation of intracranial pressure.
D000818:Animals; D001099:Arachnoid / Q000187:drug effects / Q000378:metabolism*; D001692:Biological Transport / Q000187:drug effects; D002415:Cats; D000242:Cyclic AMP / Q000494:pharmacology*; D004388:Dura Mater / Q000187:drug effects / Q000378:metabolism; D066298:In Vitro Techniques; D014667:Vasopressins / Q000494:pharmacology*; D014867:Water / Q000378:metabolism*
D014867:Water; D014667:Vasopressins; D000242:Cyclic AMP