The cavernous sinus also contains the carotid artery, which supplies blood to the brain; occasionally, compression of the artery can lead to one-sided weakness and other symptoms of stroke. Endocrine dysfunction
The pituitary gland consists of two parts, the anterior (front) and posterior (back) pituitary. Both parts release hormones that control numerous other organs. In pituitary apoplexy, the main initial problem is a lack of secretion of adrenocorticotropic hormone (ACTH, corticotropin), which stimulates the secretion of cortisol by the adrenal gland. This occurs in 70% of those with pituitary apoplexy. A sudden lack of cortisol in the body leads to a constellation of symptoms called "adrenal crisis" or "Addisonian crisis" (after a complication of Addisons disease, the main cause of adrenal dysfunction and low cortisol levels). The main problems are low blood pressure (particularly on standing), low blood sugars (which can lead to coma) and abdominal pain; the low blood pressure can be life-threatening and requires immediate medical attention.Hyponatremia, an unusually low level of sodium in the blood that may cause confusion and seizures, is found in 40% of cases. This may be caused by low cortisol levels or by inappropriate release of antidiuretic hormone (ADH) from the posterior pituitary. Several other hormonal deficiencies may develop in the subacute phase. 50% have a deficiency in thyroid-stimulating hormone (TSH), leading to hyposecretion of thyroid hormone by the thyroid gland and characteristic symptoms such as fatigue, weight gain, and cold intolerance. 75% develop a deficiency to gonadotropins (LH and FSH), which control the reproductive hormone glands.
Research shows at least 10 differences in MC1R between African and chimpanzee samples and that the gene has probably undergone a strong positive selection (a selective sweep) in early Hominins around 1.2 million years ago. This is consistent with positive selection for the high-eumelanin phenotype seen in Africa and other environments with high UV exposure. Light skin
For the most part, the evolution of light skin has followed different genetic paths in European and East Asian populations. Two genes, however, KITLG and ASIP, have mutations associated with lighter skin that have high frequencies in both European and East Asian populations. They are thought to have originated after humans spread out of Africa but before the divergence of the European and Asian lineages around 30,000 years ago. Two subsequent genome-wide association studies found no significant correlation between these genes and skin color, and suggest that the earlier findings may have been the result of incorrect correction methods and small panel sizes, or that the genes have an effect too small to be detected by the larger studies. KITLG
The KIT ligand (KITLG) gene is involved in the permanent survival, proliferation and migration of melanocytes. A mutation in this gene, A326G (rs642742), has been positively associated with variations of skin color in African-Americans of mixed West African and European descent and is estimated to account for 15–20% of the melanin difference between African and European populations.