The effect of serotonin and transcapillary pressure on the capillary permeability in the rete mirabile of the eel (Anguilla vulgaris l.).
Measurements of transcapillary exchange of high-molecular dextrans, K+ and THO in the rete mirabile of eel (Anguilla vulgaris L.) have been made under steady-state conditions while the transcapillary pressure was varied and pharmaca added to the perfusates. Raising the transcapillary input pressure increased the exchange of dextrans and K+ but lowered that of THO. Histamine and ouabain had no effect on the transcapillary exchange of the test molecules. The highest dose (100 mug/ml) of serotonin reversibly increased the capillary permeability of D-75 000, K+ and THO while the medium dose (50 mug/ml) only raised the transcapillary exchange of K+ and THO. The lowest dose (10 mug/ml) had no permeability effect. Our main conclusion is that serotonin reversibly increases the area of the intercellular pores by affecting the capillary wall directly.
D000400:Air Sacs / Q000502:physiology; D000818:Animals; D002199:Capillary Permeability / Q000187:drug effects*; D003911:Dextrans / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004524:Eels / Q000502:physiology*; D006632:Histamine / Q000494:pharmacology; D006874:Hydrostatic Pressure; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D012701:Serotonin / Q000008:administration & dosage / Q000494:pharmacology*
D003911:Dextrans; D012701:Serotonin; D010042:Ouabain; D006632:Histamine; D011188:Potassium