Kucerova Jana, Vrskova Dagmar, Sulcova Alexandra
Department of Pharmacology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
Neuro Endocrinol Lett. 2009;30(5):663-70.
The female animals were already recorded to respond differently to methamphetamine (MET) abuse than males. This gender dissimilarity may be caused by the influence of estral cycles and different susceptibility to behavioural sensitization.
Influences of gender and pre-exposure to MET were studied in the rat model of MET intravenous self-administration (IVSA). The fixed ratio (FR) paradigm was employed in male rats (M) and estrogenized (F-ESTR) and non-estrogenized ovariectomized female rats (F-OVX) either pre-exposed or not-exposed to MET pretreatment.
In rats that were not pre-exposed to MET, F-ESTR self-administered more MET infusions than each of the other groups, but F-OVX self-administered less than each of the other groups; the same trend was apparent in the MET pretreated groups. MET pre-exposure decreased subsequent MET IVSA in all groups except F-OVX.
Thus, pre-exposure to MET and the loss of inherent estrogen in females notably decreased the intake of MET by rats, suggesting that abuse liability was reduced. Estrogen's effects on MET self-administration here correspond with accumulating evidence of stronger behavioural responses of females to drugs of abuse.
已有记录表明，雌性动物对甲基苯丙胺（MET）滥用的反应与雄性不同。这种性别差异可能是由发情周期的影响以及对行为敏化的不同易感性所致。
在MET静脉自我给药（IVSA）大鼠模型中研究性别和预先接触MET的影响。对雄性大鼠（M）以及预先接触或未接触MET预处理的雌激素化雌性大鼠（F-ESTR）和未雌激素化的去卵巢雌性大鼠（F-OVX）采用固定比率（FR）模式。
在未预先接触MET的大鼠中，F-ESTR自我给药的MET输注量比其他各组都多，但F-OVX自我给药的量比其他各组都少；在MET预处理组中也出现了相同的趋势。除F-OVX外，预先接触MET会降低所有组随后的MET IVSA。
因此，预先接触MET以及雌性动物体内固有雌激素的丧失显著降低了大鼠对MET的摄入量，表明滥用倾向降低。雌激素对MET自我给药的影响与越来越多关于雌性对滥用药物有更强行为反应的证据相一致。
