Key Points
- To characterize the distribution and pharmacological properties of angiotensin II receptor subtypes in developing human fetal adrenal glands compared to adult glands.
- Examined fresh-frozen human fetal adrenals from 14 to 21 weeks of gestation alongside adult adrenal tissue sections.
- Performed autoradiography, competition binding assays, and Scatchard analyses using the AT1 antagonist DUP 753 and the AT2 antagonist PD 123319.
- Fetal adrenal receptors were predominantly AT2 with high affinity (Kd = 0.68 ± 0.1 nM), whereas AT1 receptors emerged at the adrenal periphery only after 16 weeks of gestation.
- AT2 receptor binding capacity fell from 1080 ± 304 fmol/mg protein at 14 weeks to 275 ± 55 fmol/mg protein at 21 weeks of gestation.
- Adult adrenal tissue exhibited distinct localization, confining AT1 receptors primarily to the zona glomerulosa and AT2 receptors mainly to the medulla.
Structured PICO
PPopulationHuman adrenal glands (fetal from 14 to 21 weeks gestation, and adult)
IInterventionAutoradiographic studies and co-incubations with DUP 753 (AT1 antagonist) and PD 123319 (AT2 antagonist)
OOutcomeDistribution and binding capacities of AT1 and AT2 receptorssurrogate
AT2 receptors are predominantly expressed in the human fetal adrenal gland and may be involved in its morphological or functional differentiation, differing from adult expression patterns.