12. ENDOCRINAL HYPERTENSION

Question 1

ENDOCRINAL HYPERTENSION definition?

Answer 1

It is a hypertension caused by an absolute or a relative abundance of hormones with pressor effect or
by an abnormality of the hormonal balance that affects some components of the regulatory
mechanisms which influence the blood pressure.

Question 2

Pheochromocytoma?

Answer 2

Pheochromocytomas are catecholaminesecreting tumors of neuroendocrine cells (usually in the
adrenal medulla).
It is a disease caused by an
autonomic overproduction of catecholamines by the chromaphilic cells tumor of the sympatoadrenal
system. These are usually benign tumors. Most of the pheochromocytomas produce noradrenalin
and adrenaline. In nearly 90 % of cases the tumor is situated in the adrenal medulla; in the remaining
10 % it is situated in the area of the abdominal aorta, and less common in other places. Adrenaline
stimulates mostly the beta-receptors and increases the minute cardiac output. Noradrenalin via the
alpha receptors increases the peripheral vascular resistance

Question 3

Pheochromocytoma
(Hypertension can be manifested in three different forms:?

Answer 3

1. As a permanent hypertension (in nearly half the patients)
2. As a permanent hypertension with paroxysms of increasing values of the blood pressure
3. As paroxysmal hypertension (with otherwise normal blood pressure). The course of
   permanent hypertension is very much similar to the course of essential hypertension. The
   paroxysmal forms of the disease threaten the patients with the cerebrovascular accidents,
   myocardial infarction, and heart failure.

Question 4

Adrenocortical dysfunction definition?

Answer 4

n. It is a case of hypertension with an absolute or a relative overproduction
(or inversely – an insufficiency) of some hormones of the adrenal cortex. There are two types of
hypertension that are caused by an adrenocortical dysfunction:
1. Primary hyperaldosteronism. It is a disease caused by an primary overproduction of
aldosterone in the adrenal gland (benign adenoma, malignant tumors, bilateral hyperplasia), which
differs from the secondary hyperaldosteronism, that occurs as a result of an overstimulation of the
renal cortex by the system renin – angiotensin and by other primary diseases (e.g. nephrotic
syndrome, liver cirrhosis, cardiac insufficiency, an advanced essential and renal hypertension). An
overproduction of aldosterone in primary hyperaldosteronism is responsible for all the clinical and
the laboratory characteristics of the disease, which become normal after its removal. A long lasting
overproduction of aldosterone can be manifested by:
* Arterial hypertension, and by increase of the extracellular Na+ content with a predisposition
for hypernatriemia
* Hypokaliemia with alkalosis (a result of a long lasting potassium depletion are some
neuromuscular changes such as spasm, and the development of kaliopenic nephropathy). The raise
of Na+ content and of the extracellular volume leads to (by a feedback mechanism) the lowering of
the plasma renin activity, however not to a point that causes a clinically manifested edema. And so in
arterial hypertension caused by the primary aldosteronism there are: – increased of Na+ content and
of the extracellular volume – high level of aldosterone in the plasma and urine – suppression of the
plasma renin activity
Since the description of primary hyperaldosteronism in 1955 by Conn, it was shown that it is not a
unified syndrome, but this disease has at least three subtypes:
* The classical Conn’s syndrome, when the aldosterone overproduction is caused by an
aldosterone producing adenoma, less common by a carcinoma affecting one adrenal gland.
* Idiopathic hyperaldosteronism – in cases of micro- or macronodular hyperplasia of both
adrenals.
* Dexamethasone – suppressible hyperaldosteronism (Murlow’s). It is a rare overproduction of
aldosterone by hyperplastic or normal adrenals in children. Hypertension in this case can be
stabilized only by supplementation of Dexamethasone that will inhibit the overproduction of
aldosterone by a feedback mechanism.
2. Cushing syndrome. Hypertension results from the overproduction of glucocorticoids and
sometimes also the mineralocorticoids. They could be produced by tumors or hyperplasia of the
adrenal cortex, and also by adenoma of the adenohypophysis.
e hypertension is a result of the overproduction of glucocorticoids, that increase the sensitivity of
the vascular wall to endogenous pressor factors and most probably they also change the contractility
of the myocardium and so increase of the cardiac output. Cortisol also stimulates the formation of
angiotensinogen in the liver and that is the reason why there is an increase of the plasma angiotensin
concentration. The
overproduction of mineralocorticoids promotes its effect via the Na+ retention.

Question 5

Hypertension that accompanies other endocrinopathies?

Answer 5

1. Acromegaly. It is due to the overproduction of growth hormone most commonly in cases of
   adenoma of the adenohypophysis. this disease is accompanied by the hypertension which does not
   differ from the essential hypertension. The cardiomegaly corresponds with the level of hypertension.
2. Hyperparathyroidism. An increased production of parathormone can be most commonly
   seen in cases of the parathyroid glands adenoma. The early renal complications that occur in
   hyperparathyroidism can play an important role in the development of hypertension.
3. Hyperthyroidism. An over function of the thyroid gland can also be accompanied by
   hypertension. In cases of hyperthyroidism it is usually a systolic hypertension with a high cardiac
   output (volume hypertension). Hypertension as well as other common cardiac complications are
   caused by the direct effect of the thyroid hormones on the myocardium.
4. Diabetes mellitus. The relation between hypertension and diabetes is well known for over 60
   years. The presence of hypertension is more common in cases of non-insulin dependent diabetes
   (type II) where it correlates with age, obesity, and with the drop in the renal function. Pathogenesis
   of this hypertension is quite. Many factors play a role here: e.g. renal factors, macro- and
   microangiopathy, renin- angiotensin-aldosterone system and catecholamines.