[Radioimmunological analysis of 17 beta-estradiol and the effect of physical exertion on its levels in human blood].

: A procedure is described for quantitative radioreceptor estimation of opioid peptides in rat brain using lyophilized membrane preparations. As opiate receptors exhibit high rate of heterogeneity estimation of delta- and mu-opioid activities was carried out by means of displacing of 3H-DADLE and 3H-DAGO, respectively. Content of opioid peptides in brain of preadolescent rats was studied during experimental burn trauma using the procedure developed. An increase in the delta- and mu-opioid activities was found in rat brain tissue within one day after thermal burns.