On the selection of in vitro thyroid function tests

Prenatal hypoxia attenuated contraction of offspring coronary artery associated with decreased PKCβ Ser660 phosphorylation and intracellular calcium

AIMS

Prenatal hypoxia (PH) could affect peripheral vascular tone of the offspring, thus increasing the risk of cardiovascular diseases in adult. However, it's still unknown whether functions of coronary arteries (COA) in adult offspring would be influenced by PH. The present study aimed at effects of PH on vascular tone of COA and its related mechanisms.

METHODS

Coronary arteries of adult offspring exposed to hypoxic or normoxic circumstances during gestational day 5 to 21 were collected. Wire myograph system, whole-cell patch clamp technique, IonOptix MyoCam system, PCR, and western blot were used to detect vascular function of adult offspring COA.

KEY FINDINGS

PH significantly attenuated serotonin- and phorbol 12, 13-dibutyrate (PDBu)-induced constriction. Iberiotoxin potentiated PDBu-induced constriction and the effect was augmented by PH, however, no significant differences were found in whole-cell BK_Ca channel currents and its protein expression. Nifedipine inhibited PDBu-mediated constriction and the inhibitory effect was reduced in PH group, and whole-cell calcium channel current was decreased in offspring COA. Besides, PH reduced the capability of calcium release from the endoplasmic reticulum in COA. The phosphorylated PKCβ protein expression at Ser⁶⁶⁰ site, not Thr⁶⁴¹ site, was significantly decreased in PH offspring. Chronic hypoxia during pregnancy attenuated PDBu-mediated constriction in offspring COA, presumably through decreased phosphorylated PKCβ at serine⁶⁶⁰ sites and decreased intracellular calcium-related weaker PKC activation.

SIGNIFICANCE

The findings provided new information on the influence of prenatal hypoxia on COA, and suggested potential use of PKCβ-serine⁶⁶⁰ for early prevention of coronary heart diseases in developmental origins.

Diagnostic usefulness of cerebrospinal fluid in multiple sclerosis

Multiple sclerosis (MS) is one of the most common demyelinating diseases of the central nervous system affecting adults between the ages of 20 and 40 years. Clinically, it is characterized by episodes of exacerbations and remissions. Although the cause of MS is unknown, it is generally believed that one or more infectious agents triggers an autoimmune response that causes myelin destruction. There is no known cure for this disease; however, early diagnosis is helpful in the management of patients with MS. The diagnosis of MS is commonly made on the basis of established clinical criteria. No specific laboratory diagnostic test exists, but detection of abnormalities in cerebrospinal fluid (CSF) is a useful aid to support the clinical diagnosis of MS. This review describes the most common CSF abnormalities. These include (a) elevation of immunoglobulin G (IgG), IgG index and IgG synthesis rate; and (b) detection of oligoclonal IgG bands in the CSF by electrophoresis and isoelectric-focusing procedures.

Serum thyroxine, triiodothyronine and thyroid stimulating hormone after prolonged heavy exercise

Serum thyroxine (T4), triiodothyronine (T3) and thyroid stimulating hormone (TSH) was measured before, immediately after and on the following days after a 70 km cross-country ski race in two groups of ten well-trained men, one aged 21--29 years, taking 5.01--7.03 h, and one aged 51--57 years, taking 6.07--7.38 h. T4 was definitely increased immediately after the race, but fell to below the initial level on the following day and was not restored to the pre-race level until 4 days after the race. T3 showed essentially the same pattern, though less pronounced, a major part of the changes being possibly due to plasma volume variations. TSH showed a tendency to rise immediately after the race, but rose further to 175% of the initial level on the following day and was not restored to the initial level 4 days after the race. The pattern of changes were independent of age. It is suggested that the prolonged rise in TSH is probably due to an exercise-induced increased peripheral need for thyroid hormone.