A heterogeneous population of alpha 1-adrenoceptors mediates contraction of the isolated follicle wall from the bovine ovary

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

Strips from Graafian follicles of bovine ovaries were tested for their contractile response in vitro in order to characterize the type of post-junctional alpha-adrenoceptor involved. Electrically induced contractions were inhibited concentration-dependently by the alpha 1-antagonist, prazosin. Besides noradrenaline the alpha 1-selective agonists, methoxamine and phenylephrine, caused the strips to contract, whereas the alpha 2-selective agonists clonidine, oxymetazoline and B-HT920 were without effect. However, the alpha 1-selective antagonist prazosin gave a line with a slope less than unity in the Schild plots with noradrenaline and methoxamine. From results obtained with or without the presence of two classes of neuronal uptake blockers (desipramine and cocaine) it is concluded that the post-junctional alpha 1-receptor population is inhomogeneous. The regular appearance of the Schild plot obtained with phenylephrine may be due to involvement also of a component of noradrenaline release by this agonist. The pA2 value in the test with phenylephrine was 9.27, with a corresponding kB of 3.81 +/- 1.15 X 10(-10) M.

Detaljer

Författare
Enheter & grupper
Externa organisationer
  • Lund University
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Farmakologi och toxikologi
Originalspråkengelska
Sidor (från-till)563-571
TidskriftActa Physiologica Scandinavica
Volym133
Utgåva nummer4
StatusPublished - 1988
PublikationskategoriForskning
Peer review utfördJa