I Love L-arginine

[Bill Gates]

Read this study.

L-arginine, the substrate of nitric oxide synthase, inhibits fertility of male rats.

Ratnasooriya WD, Dharmasiri MG.

Department of Zoology, University of Colombo, Sri Lanka. dappvr@sltnet.lk

AIM: To examine the effect of L-arginine, the substrate of nitric oxide (NO) synthase, on reproductive function of male rats. METHODS: Male rats were gavaged with either L-arginine (100 or 200 mg x kg(-1) x d(-1)), D-arginine (200 mg x kg(-1) x d(-1)) or vehicle (0.9% NaCl) for seven consecutive days. Their sexual behaviour and fertility were evaluated using receptive females. RESULTS: L-arginine (200 mg/kg) had no significant effect on sexual competence (in terms of sexual arousal, libido, sexual vigour and sexual performance). In mating experiments, the higher dose of L-arginine effectively and reversibly inhibited fertility, whilst the lower dose and the inactive stereoisomer D-arginine had no significant effect. The antifertility effect caused by L-arginine was due to a profound elevation in the preimplantation loss mediated possibly by impairment in epididymal sperm maturation, hyperactivated sperm motility and sperm capacitation. CONCLUSION: Elevated NO production may be detrimental to male fertility.

PMID: 11404792 [PubMed - indexed for MEDLINE]
Asian J Androl. 2001 Jun;3(2):97-103.

[Styleee]

Interesting... exactly how high were they going with elevated dosages though? Could be far over what we take for bodybuilding...

[Bill Gates]

This is the Full Text Link:
http://www.asiaandro.com/1008-682X/3/97.htm

It's Free

[Bill Gates]

This is the Authors Conclusion:

In conclusion, this study demonstrates, for the first time, that L-arginine inhibits fertility without compromising sexual competence of male rats. This observation could have important implications in the development of male contraceptives. Thus, it is worthwhile to extend these studies to spontaneous NO donors. Our results also provide further evidence in favour of the link between NO and male fertility.

[Styleee]

None of the reproductive parameters tested was significantly altered, both with the lower dose of L-arginine and D-arginine. In contrast, with the higher dose of L-arginine, quantal pregnancy (day 1, by 56%; day 3, by 57% and day 7 by 57%), number of implants (day 1, by 82%; day 3, by 52% and day 7, by 61%), implantation index (day 1, by 80%; day 3, by 52% and day 7, by 56%) and fertility index (day 1, by 89%; day 3, by 56% and 57%) were significantly reduced, and the pre-implantation loss was significantly enhanced (day 1, by 738%; day 3, by 385% and day 7, by 617%). Seven days after cessation of the treatment, these parameters returned or closed to normal. There was no post-implantation loss.

So lower dosages would not have a negative effect on fertility, but high dosages would... only temporarily.

I don't really think this is something to worry about unless you are megadosing L-arginine for very long periods of time. Just take what is needed to get an effect, that's all.

[Bill Gates]

So lower dosages would not have a negative effect on fertility, but high dosages would... only temporarily.

I don't really think this is something to worry about unless you are megadosing L-arginine for very long periods of time. Just take what is needed to get an effect, that's all.

The problem with study is the rats & I don't think we will see a similar study on humans (scientists won't risk on people health), maybe lower dosages are not harmfull, but what about long term lower dosages L-arginine supplementation?

[pu12en12g]

Great post man We've been saying this for awhile now...

http://forum.bodybuilding.com/showthread.php?t=253454

[Bill Gates]

Great post man We've been saying this for awhile now...

http://forum.bodybuilding.com/showthread.php?t=253454

Thanks for the link