Physiological increases in lactate inhibit intracellular calcium transients acidify myocytes and decrease force in term pregnant rat myometrium

摘要

Key points class="unordered" style="list-style-type:disc" id="tjp6794-list-0001">Lactate is increased in myometrial capillary blood from women in slow or non‐progressive labour (dystocia), suggesting that it is detrimental to uterine contractions.There are no studies of the effect of lactate on the myometrium. In the present study, we have investigated its effects and mechanism of action on myometrial strips from term pregnant rats.We show that lactate significantly decreased spontaneous contractility. Lactatedecreased pHi and inhibited Ca²⁺ transients. Nulling the decrease in pHi abolished the effects of lactate effects. If Ca²⁺ entry was enhanced, the effects of lactate were abolished.The present study suggests that the accumulation of extracellular lactate could contribute to labour dystocia.