Mounting and receptive behavior in the ovariectomized female rat: Influence of estradiol,dihydrotestosterone, and genital anesthetization

Two experiments were performed with ovariectomized female rats in an attempt to determine whether estradiol and dihydrotestosterone work synergistically in the brain to activate mounting behavior. In Expt 1, performed in Göteborg, it was found that females treated daily with 2 μg estradiol benzoate (EB) combined with 500 μg dihydrotestosterone (DHT) displayed significantly more mounts with pelvic thrusting than other females treated with the oil vehicle, 500 μg DHT, or 2 μg EB. The behavior of rats receiving EB + DHT was indistinguishable from that of yet another group of females which received 200 μg testosterone propionate (TP). In Expt 2, performed in Rotterdam, it was found that ovariectomized female rats treated with either 200 μg TP or 2 μg EB + 200 μg dihydrotestosterone propionate (DHTP) mounted significantly more than females treated with 2 μg EB. Both clitoral size and the growth of cornified papillae on the glans clitoris were stimulated by the administration of TP or EB + DHTP. However, in no group was the frequency of mounting affected by anesthetization of the clitoris and external vagina with lidocaine paste. Lordosis quotients of females treated with EB + DHTP were significantly lower than in rats receiving either EB or TP, again regardless of whether or not the genital region was anesthetized. It is concluded that the effects of DHT on estradiol-induced mounting and receptivity most likely result from the action of this androgen on the brain, and not from the stimulatory effect which DHT may exert on genital sensory receptors.     

Peptides with NH2-terminal tryptophan in the adenohypophysis

Summary In the mammalian pituitary formaldehyde-ozone treatment induces strong fluorescence in the cells of the pars intermedia and moderate to strong fluorescence in numerous cells of the pars distalis. Maximum excitation is at 370–375 nm and maximum emission at 495–505 nm. The properties of the cellular fluorescence are indistinguishable from those of tryptamine or peptides with NH₂-terminal tryptophan. From chemical analysis such peptides seem to occur abundantly in the mammalian pituitary. The concentration of these peptides agrees very well with the number and fluorescence intensity of the cells in all species studied. Furthermore, the tryptophyl peptides in the various parts of the pig pituitary have a distribution quite parallel to that of the fluorescent cells. As we have failed to detect tryptamine in the pituitary, we conclude that the formaldehyde-ozone-induced fluorescence in the adenohypophysis reflects the presence of tryptophyl peptides.This study was supported by grants from the Swedish Medical Research Council (04X-1007; 04X-3764), the Ford Foundation, Harald and Greta Jeanssons stiftelse and Riksföreningen mot Cancer (660-K73-01X).For brevity occasionally referred to as tryptophyl peptides.     

Degradation of polysaccharides containing uronic acid residues

A method for the selective degradation of polysaccharides containing uronic acid residues is described. It involves methylation of hydroxyl and carboxyl groups, base-catalysed elimination, and mild hydrolysis with acid. The degraded product is etherified with trideuteriomethyl or ethyl groups and hydrolysed, and the resulting mixture of etherified sugars is analysed, as the alditol acetates, by g.l.c.—m.s. Comparison of this analysis with the methylation analysis of the original polysaccharide gives information on the nature of the sugar residues on either side of the uronic acid residue.