Cerebrospinal fluid (CSF) samples obtained by cisternal puncture from rabbits within 10 min. after intravenous pentobarbitone anaesthesia contained the equivalent of 57 \ m=+-\ 5\m=.\4\g=m\-u.arginine vasopressin/ml. Treatment with thioglycollate and trypsin abolished the antidiuretic activity. Stimulation of the central end of a severed vagus raised the concentration of antidiuretic activity in the CSF significantly. After the intravenous injection of vasopressin, antidiuretic activity measured in blood and CSF rose quickly, but the levels attained in the CSF were always lower than those in blood.When CSF samples were obtained with local anaesthesia no antidiuretic activity could be demonstrated; i.e. in terms of the sensitivity of the assay procedure used these samples contained less than the equivalent of 4\m=.\2 \g=m\-u. vasopressin/ml. The significance of these findings is discussed in connexion with the morphological evidence suggesting the secretion of neurohypophysial hormones by neurosecretory neurones into the 3rd ventricle.

Hypothyroidism is associated with mental and growth abnormality in children. The aim of this study was to determine the reference range of thyroid stimulating hormone (TSH). Thyroxin (T4) and triodothyronine (T3) of children in Northern Iran. The sample population for this study consists of subjects of 4 age groups up to 21 years. The subjects were selected randomly from people referred to Danesh Medical Diagnostic Laboratory in Gorgan Northern Iran. Thyroid hormone level were investigated with Radio immunoassay. The mean concentration for T4, T3, TSH for the sample population of 4 groups were as follow (113.5, 107.4, 102.9, 99.2 nmol L(-1)), (1.9, 1.7, 1.9, 1.6 nmol L(-1)) and (2.1,3.5, 2.9, 2.7 mIu L(-1)). The mean value of T3, TSH were higher for females but the mean value of T4 was slightly higher in males. The findings of this investigation indicated that there is an inverse age correlation in particular for T4 in all age groups. On the bases of the results from this study, we conclude that reference range, in all age groups and lower, upper limits of our reference range are not universally similar; therefore determination of reference range in each region is a critical need for clinical practice.

The objective of this study was to evaluate the urinary iodine concentration in Gorgan located in northern Iran, which is a cosmopolitan society and on the basis of such determination the endemic goiter in the region could be estimated. The sample population were a total of 287 people (23.3% male, 76.7% female) referred to Danesh Medical Diagnostic Laboratory for the urinary iodine measurement, during 2004-05. Urinary iodine level was determined using acid digestion method. The results from this study indicated that 2.1, 3.8 and 9.8% of sample population had urinary iodine level of <2, 2-4.9 and 5-9.9 microg dL(-1), respectively which are defined as sever, moderate and mild iodine deficiency. Therefore 45 (15.7%) of the sample population in this study could be assessed for goiter prevalence, the mean differences of iodine concentration in male and female subjects were not significant. In conclusion, low urinary iodine of <10 microg dL(-1) concentration may help to give a direction for a further examination in the thyroid gland abnormalities.

The purpose of this study was to describe the distribution of serum prostate specific antigen (PSA) and to determine age-specific reference range in a population of Persian men. Venous blood samples were taken from 287 men, from Gorgan located in the North of Iran, South-East of Caspian Sea, aged 15 > or = 80 year. The serum PSA levels was measured using Enzyme-linked Immunosorbant-Assay (ELISA) technique and age-specific range for PSA level was determined. The serum prostate-specific antigen level for six age group of 15-40 years, 41-50 years, 51-60 years, 61-70 years, 71-80 years and >80 years were mainly in the range of 0-2.5 ng mL(-1), for 76.6%, 2.6-4 ng mL(-1) for 9.1% and as whole 85.7% of all men in this study had < or = 4 ng mL(-1), 8.7 and 5.6% all men of six age group had PSA level of 4.1-10 ng mL(-1) and >10 ng mL(-1), respectively. The findings of present study indicated that a large proportion (76.6%) men in this region have a lower PSA level of 0-2.5 ng mL(-1) and only 9.1% of men have PSA level of 2.6-4 ng mL(-1). It is therefore concluded that acceptable reference range of 0-4 ng mL(-1) for PSA level require further reassessment.

Many metabolic disorders originate from thyroid disorders, particularly from hypothyroidism. Hypothyroidism commonly occurs in elderly subjects, particularly in women. Subclinical form of hypothyroidism can be diagnosed via laboratory testing. It is crucial to check thyroid hormone profile in elderly subjects. Subclinical hypothyroidism can eventually lead to overt hypothyroidism if left untreated. Treatment of subclinical hypothyroidism could be helpful in preventing the complications of hypothyroidism, particularly among the elderly population. The main aim of this review was to investigate subclinical hypothyroidism among elderly subjects.