If you glaze fired to a hotter temperature than the bisque, it is possible that more carbon would burn out during glaze firing, causing blisters in the glaze which would not have time to heal over. For some clays this is not a problem. The carbon content in the clay is low or burns out early.
Catecholamines are derived from the amino acid tyrosine, which is derived from dietary sources as well as synthesis of phenylalanine. Catecholamines are water-soluble and are 50%-bound to plasma proteins in circulation.
The catecholamine metabolites vanillylmandelic acid and homovanillic acid can be measured quantitatively in the urine as a test for the disease. Pheochromocytoma is a benign tumor derived from the adrenal medulla or sympathetic paraganglia. The tumor secretes epinephrine and norepinephrine. These catecholamines cause attacks of hypertension, headache, nausea and vomiting, sweating, pallor and severe apprehension.