PMS-A is the most common PMS symptom category and is related most strongly to an estrogen excess and progesterone deficiency in the luteal phase. Symptom ratings correspond to the raised serum estrogen levels, and serum estrogen to progesterone ratios give the best correlation. There is no significant correlation of symptoms with the decreased progesterone levels.
Causes and Development
Estrogens appear to affect mood by suppressing type A-monoamine oxidase (MAO
) while enhancing type B-MAO. These enzymes are involved in the oxidation of biogenic amines - norepinephrine
, and serotonin
- which have significant effects on mood and behavior. The net effect of estrogen
on these MAOs is to increase the levels of epinephrine, norepinephrine and serotonin (all normally deactivated by MAO-A) and decrease the levels of dopamine and phenylethylamine (both normally metabolized by MAO-B).
The effects of these changes on mood and behavior are well documented: epinephrine triggers anxiety
; norepinephrine, hostility and irritability; serotonin, at high levels, nervous tension, drowsiness, palpitations, water retention and inability to concentrate and perform. Dopamine is believed to counteract these three amines by inducing a feeling of relaxation and increasing mental alertness. It is of interest to note that a decreased dopamine level in the hypothalamus
is also believed to be central to the hormonal imbalances found in polycystic ovarian disease.
Estrogens also affect mood by competing for pyridoxal-5-phosphate binding sites, stimulating hepatic tryptophan
pyrolase (shunting away from serotonin
synthesis), and decreasing glucose