[The role of adrenergic receptors in the regulation of blood flow in the reproductive organs of swine during the estrous cycle].

Abstract

The dimension of flow in uterine artery (ua) and ovarian artery (oa) was measured. It was conducted in the isolated porcine (100-130 kg/per head) reproductive organs perfused with their own blood or Krebs-Henseleit fluid when the pressure was kept on the constant level 100 m Hg. Phenoxybenzamine (Ph), phentolamine (R), propranolol (P), pronetalol (Pr) were used and also after them adrenaline (A), noradrenaline (NA) or isoprenaline (I) were administrated. Changes in blood flow (bf) through the organs connected with inhibition or stimulation of adrenergic receptors during estrous cycle were analysed. It was stated that R increased bf, but not significantly. Ph increased significantly bf in the reproductive organs and blocked decreasing bf influence of A and NA in ua and oa areas. Both A and I administrated after Ph and R caused the increase in bf in the both investigated vessel areas. Beta-adrenolytic agents P and Pr decreased bf and also blocked increasing bf action of I. When we used A or NA after P or Pr administration, there was observed significant limitation of bf in the reproductive organs. Reactions evoked by alpha- and beta-adrenergic stimulation were different during estrous cycle. The highest activity of alpha receptor--which dominates the vessels of porcine reproductive organs--was found in the luteal phase of cycle where the activity of beta receptor was the lowest. The activity of alpha receptor decreased and increased activity of beta receptor in the pre and postovulatory phase of cycle compared to the state observed in the luteal phase. Beta receptor did not play any significant role in the regulation of bf in the porcine reproductive organs. Data from references discussed in this work and our results suggest that regulation of sensitivity of vessels in the porcine reproductive organs was not connected with quantitative representation of adrenergic receptors. Changes of vessel sensitivity were connected with changes of alpha-adrenergic receptor activity.