Probable neuro sexual mode of action of Casimiroa edulis seed extract versus [correction of verses] sildenafil citrate (Viagra(tm)) on mating behavior in normal male rats.

The present study deals with the aphrodisiac actions of the aqueous extract of the seeds of the hypotensive plant Casimiroa edulis on the sexual behavior of normal male rats. In this investigation 30 healthy male Wister strain white albino rats showing the brisk sexual activity age 15 weeks, weighing 400-450 grams were included. Female rats were artificially brought into estrous by hormonal treatment. Receptivity was checked by exposing them to the male rats and the most receptive females were selected for the stud The mating responses including Mounting Frequency (MF), Intromission Frequency (IF), Mounting Latency (ML), Intromission Latency (IL), Ejaculatory Latency in first and second series (EL1 and EL2) and Post Ejaculatory Interval (PEI) were recorded after treating the animals with 250 mg/kg casimiroa edulis extract (test reference) and 5 mg/kg sildenafil citrate (standard reference) respectively orally per day for 7 days. Both the groups exhibited a significant increase in Mounting Frequency, Intromission Frequency, and first and second ejaculatory latencies, where as Mounting and Intromission latencies and the Post Ejaculatory Interval showed a significant reduction than the controls. Although a similar pattern of mating behavior was observed among the test and the standard groups, however in all the cases as expected, sildenafil produced greater activity than the casimiroa edulis extract. These results suggest the possibility of a similar mode of action of casimiroa edulis and sildenafil citrate on mating behavior in these animals. Our work reported in this research thus provide preliminary evidence that the aqueous seed extract of casimiroa edulis possesses alphrodisiac activity and may be used as an alternative drug therapy to restore sexual functions probably via a neurogenic mode of action.

Neurophysiological role of sildenafil citrate (Viagra) on seminal parameters in diabetic males with and without neuropathy.

Sildenafil citrate is a specific inhibitor of phosphodiesterase (PDE) type-5 and represents a powerful therapy for male erectile and fertility dysfunctions of different etiologies. Present study demonstrates whether sildenafil administration modifies seminal parameters in diabetic neuropathic patients. In this investigation 50 insulin dependent (IDDM) and 50 non insulin dependent (NIDDM) diabetic male patients with and without an objective evidence of neuropathy and 50 age matched non diabetic male controls were selected. Every male had age between 20 to 65 years with duration of diabetes distributed over 1 to 20 years. Treatment with 100 mg of oral sildenafil citrate on seminal parameters was evaluated by semen analysis in these patients. In both IDDM and NIDDM diabetic neuropathic patients, chronic sildenafil treatment exhibited a significant decrease in total sperm output and sperm concentration (p<0.001). On the other hand, sperm motility and semen volume were found to be increased by about 40% and 48% respectively in these patients, where as sperm morphology and quality of sperm motility remained unaffected. However both types of non neuropathic diabetics showed a non significant difference in all the above mentioned parameters when compared with the untreated groups and their respective control subjects. A comparison between IDDM and NIDDM neuropathic and non neuropathic diabetic groups further indicated a non significant difference in all the parameters of semen analysis. These findings suggest a chronic neuro physiological effect of sildenafil treatment on male fertility profile exclusively in diabetic neuropathic condition with an improvement in testicular function which was probably arrested due to some kind of testicular hyperplasia resulted by testicular necrosis and promoted spermatogenesis. Sildenafil seems to be associated with an improvement in the entire smooth musculature of reproductive tract and testicular morphology which was altered due to neuropathy like a reduction in excess accumulation of interstitial collagen and calcification in the smooth muscles of seminiferous tubules which made them rigid leading to atonia of bladder and urethra which resulted in partial or retrograde ejaculation associated with a decreased sperm motility. Sildenafil treatment returned back the spermatogenesis to normal with a positive influence on sperm motility and ejaculate volume in these neuropathic patients irrespective of the type of diabetes.

The inherent rhythmic contraction property of penile tissue in sexually active adult male rats and the effect of sildenafil citrate (Viagra): an in vitro pilot study.

Isolated human cavernosal muscles and those of various animals have extensively been studied for understanding the causes and treatment of erectile dysfunctions. Usually these tissues are first pretreated with suitable drugs, i.e. Noradrenaline (N-Adr), phenylephrine, carbacol, KCl and nicorandil etc. to induce resting tone or contractions in them, followed by the application of relaxing drugs like sildenafil. We undertook this project to show first of all that these penile tissues were capable of generating rhythmic contractions if properly treated with suitable drugs, either alone or in combination, and then to study the properties of these induced tensions and/or contractions. Attempt was also made to study the effects of sildenafil on various parameters of these contractions. Pretreatment of the tissues with atropine and N-Adr both initiated rhythmic contractions, the atropine effect being more potent (2-1/2 times larger) on the contraction rate while N-Adr effect being significantly higher on the resting tone. Atropine also increased the contraction rate and strength of contractions in the washed tissues or when it was applied in combination with N-Adr. Ach had no effect on the rate and strength of contractions in atropine treated tissues but it decreased contraction rat in washed tissues or when applied in combination with sildenafil. Sildenafil decreased the rate and strength of contractions in all the tissues pretreated with atropine or N-Adr or in the washed tissues. The effect of sildenafil was more potent on atropine treated tissues than those on N-Adr treated ones. Atropine, Acetylcholine (Ach) and sildenafil had no effect on the resting tone of the tissues while N-Adr significantly increased the resting tone in both the atropine treated and washed tissues.