Introduction Sexual dysfunction is significantly more prevalent in women than in men. 15.6% at 5.10?4 M vs. 16.5% at AMP 5.10?4 M under the same experimental conditions. Nitric Axitinib oxide (NO) synthase inhibitor N-nitro-L-arginine strongly inhibited the relaxing effect provoked by AMP suggesting that the action mechanism of this nucleotide is related to the NO pathway. The combination of L-Arginine at 5.10?4 M with AMP at different doses ranging from 5.10?4 M to 10?3 M significantly amplified the relaxing response up to 40.7% and 58% respectively. Conclusions Our results demonstrate that AMP induces a relaxing effect on the female rabbit corpora. They also show that L-Arginine and AMP can potentiate each other and that a synergistic effect can be obtained by their combined use. Because only slight differences exist Axitinib between both sexes in response to NO donors and/or nucleotide purines or in their use together it is very likely that close biochemical mechanisms although not to the same degree and not quite similar are involved in the engorgement of the penis and the clitoris of New Zealand White rabbits. Stücker O Pons C Neuzillet Y Laemmel E and Lebret T. Original research-sexual medicine: Effects of adenosine monophosphate used in combination with L-Arginine on female rabbit corpus cavernosum tissue. Sex Med 2014;2:1-7. < 0.05 was considered significant in all tests. All results are expressed as mean ± standard error of the mean. Results The maximal relaxing effect after addition of active substances was measured at each stage (for each concentration) and was reached in approximately 1 minute as shown in Figure ?Figure1.1. The number of single strips for each experiment was n = 12. Figure 1 Dose-response curve over time for L-Arginine (A) and adenosine monophosphate (B). AMP = adenosine monophosphate; Larg = L-Arginine; PE = phenylephrine; WO = wash-out AMP-Induced Relaxation Muscles were precontracted by PE 20 μM. Exposure of this preparation to AMP led to a significant (< 0.001) relaxation level that reached 11.7% at 5.10?4 M and 25% at 10?3 M (see Figure ?Figure22). Figure 2 AMP-induced relaxation on corpus cavernosum precontracted with phenylephrine (20 μM). Vertical bars indicate SEM (n = 12). AMP = adenosine monophosphate; SEM = standard error of the mean Axitinib When L-NNA was used before AMP the relaxation produced by AMP at 5.10?4 M and at 10?3 M was strongly inhibited i.e. limited to 6.7% and 6.9% respectively. The relaxing effect was significantly different with and without L-NNA especially at AMP 10?3 RPTOR M (= 0.009). L-Arginine-Induced Relaxation When L-Arginine was used to induce relaxation after a precontraction to PE the relaxation was 15.6% at 5.10?4 M in a concentration-dependent way (< 0.001). The results are presented in Figure ?Figure33. Figure 3 L-Arginine-induced relaxation on corpus cavernosum precontracted with phenylephrine. Vertical bars indicate SEM (n = 12). SEM = standard error of the mean AMP/L-Arginine-Induced Relaxation Precontraction with PE was induced before a concentration-dependent curve to Axitinib AMP (5.10-4 and 10-3 M) followed by different L-Arginine concentrations of (10-4 2.1 and 5.10-4 M). The results (see Figure ?Figure4)4) show that under these experimental conditions AMP induced a significant (< 0.0001) relaxation (16.5% at 5.10-4 M and 37% at 10-3 M). When L-Arginine 5.10-4 M was added the AMP-induced relaxation was significantly enhanced; at AMP 5.10-4 M a 41% relaxation was reached (vs. 16.5% without L-Arginine) and at 10-3 M a 58% relaxation was reached (vs. 37% without L-Arginine). Figure 4 AMP (5.10?4 and 10?3 M)/L-Arginine (5.10?4 M) association-induced relaxation on corpus cavernosum precontracted with phenylephrine. Vertical bars indicate SEM (n = 12). AMP = adenosine monophosphate; SEM = standard error of the ... A was demonstrated with these two compounds as the final result was superior to the addition of the two effects obtained separately (15.6% for L-Arginine alone). To confirm this result the response induced by L-Arginine alone was substracted from that induced by L-Arginine with AMP and the result compared with AMP.