Growth and Development in the Rat during Sub-Chronic Exposure to Low Levels of Hydrogen Sulfide

Abstract

The effects of low levels of hydrogen sulfide (H2S) on mammalian growth and development are unknown although it has long been postulated that H2S can inhibit critical developmental functions through the cleavage of disulfide bonds and chelation of essential metal ions. Gravid rat dams exposed to H2S (less than or equal to 75 PPM) from day 6 of gestation until day 21 postpartum (PP) demonstrated normal reproductive parameters until parturition. At parturition, however, delivery time was extended in a dose dependent manner with a maximum increase of 42% at 75 PPM. Maternal liver cholesterol content was elevated significantly on day 21 postpartum following exposure to 75 PPM H2S each day for 6 weeks. Pups which were exposed in utero and neonatally to day 21 postpartum developed with a subtle decrease in time of ear detachment and hair development and with no other observed change in growth and development through day 21 postpartum.

L‐Cysteine and Sodium Hydrosulphide Inhibit Spontaneous Contractility in Isolated Pregnant Rat Uterine Strips in vitro

“…This relaxant effect is simi- Fig. It is known that H 2 S is toxic at high concentrations (Reiffenstein et al 1992), and that it can bind to metal-containing proteins, thus potentially interfering with the contraction mechanism of smooth muscle by uncoupling the electron transport chain (Hayden et al 1990(Hayden et al & 1989. Comparison of the effect of sulphur-containing amino acids (log.…”

“…Integrals of contractions over 10 min. Levels of H 2 S, in the range 20 -75 ppm, have been shown to cause a dose-dependent increase in the duration of parturition in rats (Hayden et al 1990), suggesting that H 2 S can inhibit myometrial contractility in vivo. MeansπS.E.M.…”

“…Recently it has been reported that hydrogen sulphide (H 2 S) acts as a signalling molecule in the body (Abe & Kimura 1996). Low levels of H 2 S were found to cause a dose-dependent increase in the duration of parturition in rats, suggesting that H 2 S was able to inhibit the contractility of the myometrium in vivo (Hayden et al 1990). Sodium sulphide, a sulphide ion donor, has been shown to attenuate the contractile response of non-pregnant rat uterus to oxytocin in vitro (Hayden et al 1989).…”

L-Cysteine and Sodium Hydrosulphide Inhibit Spontaneous Contractility in Isolated Pregnant Rat Uterine Strips in vitro

“…Sodium sulphide, a sulphide ion donor, has been shown to attenuate the contractile response of non-pregnant rat uterus to oxytocin in vitro (Hayden et al 1989). Low levels of H 2 S were found to cause a dose-dependent increase in the duration of parturition in rats, suggesting that H 2 S was able to inhibit the contractility of the myometrium in vivo (Hayden et al 1990). It has been demonstrated that H 2 S is produced endogenously in various tissues from L-cysteine by two main enzymes, cystathionine b-synthase and cystathionine g-lyase (Stipanuk & Beck 1982;Griffith 1987;Erickson et al 1990;Swaroop et al 1992).…”

Hydrogen sulfide in the endocrine and reproductive systems

“…The same group later set up an in vivo study using pregnant rats, and showed that delivery time was significantly extended following exposure to low levels of H 2 S (≤75 ppm) in a dose-dependent manner at parturition [53] [54]. Srilatha et al found that NaHS significantly relaxed rabbit vaginal and cavernosal smooth muscle strips [43].…”