Pharmacokinetic-pharmacodynamic study of apomorphine's effect on growth hormone secretion in healthy subjects.

Apomorphine (APO) stimulates growth hormone (GH) release via dopamine D2 receptors (DRD2). There is no specific study assessing the relationship between APO pharmacokinetic (PK) and the pharmacodynamic (PD) response e.g.

Hedonic response to sucrose solutions and the fear of weight gain in patients with eating disorders.

Previous research has shown that patients with bulimia nervosa (B), anorexia nervosa, restricting type, or restrictive-anorectic (RA), and anorexia nervosa, binge eating, purging type, or anorectic-bulimic (AB) exhibit a reduced hedonic response to sucrose compared with control subjects. We hypothesized that this response could be linked to an excessive fear of weight gain rather than a decreased ability to experience pleasure. We therefore compared the hedonic responses to sucrose solutions in B, RA and AB women (n=20/group) in two different conditions: sucrose solution swallowed vs.

Dopaminergic drug response and the genotype (Taq IA polymorphism) of the dopamine D2 receptor.

The genotype of the receptor with which a particular drug interacts may be a between- subject factor that modifies the pharmacodynamic and consequently the therapeutic response to drugs. Subjects with A1 allele (Taq IA restriction fragment length polymorphism) of the gene encoding for the dopamine D2 receptor (DRD2) seem to express lower number of DRD2 compared to subjects who do not have this allele. We investigated whether subjects homozygous for the A1 allele of the DRD2 gene have decreased response to DRD2 stimulation by apomorphine when compared with those homozygous for the A2 allele.