Postmortem behavior of serum thyroxine, triiodothyronine, and parathormone.

Comparison of thyroxine, triiodothyronine, and parathormone levels in antemortem and postmortem sera was done by radioimmunoassay. In all but one of twelve cases, thyroxine levels irregularly declined after death, but this was statistically significant in only five patients. Triiodothyronine was assayed in eleven patients; two levels fell, six rose, and two remained unchanged as late as 17.75 h after death. One patient had a decline in hormone level, followed by an elevation. Five of the eleven patients assayed for parathormone maintained stable levels for as long as 17.75 h after death. Five levels showed an elevation, and one, a decline followed by an elevation. The erratic behavior of triiodothyronine and parathormone after death may be due to conversion from thyroxine or from heterologous forms of parathormone, respectively. It was noted that hormone levels from the inferior vena cava tended to be higher than those from femoral veins, with diffusion of hormone from decomposing glands in the neck as a possible cause.

Pi-Z phenotypes in a pulmonary clinic. Their prevalence and physiologic state.

A series of 1,458 consecutive patients referred to the Cleveland Veterans Administration Pulmonary Clinic for pulmonary function studies was evaluated for alpha 1-antitrypsin deficiency by determination of serum trypsin inhibitory capacity (STIC). Protease inhibitor (Pi) phenotyping was performed on all sera with STIC values less than 1.6 mg/ml. The following non-MM phenotypes were found: 1FZ, 32MZ, 2ZZ, 3SZ, 5SS, 33MS, 21M. The prevalence of Pi Z heterozygosity is 2.74%. This figure is not significantly greater than that observed in a healthy population. A group ( n = 12) with heterozygous Z phenotype (MZ + SZ) was compared with a control (MM) group (n = 13) matched for age, race and smoking history from this same population. Our findings indicate similar deviations from predicted normal values in both control (MM) and Z-heterozygotic groups for physiologic tests of airway resistance, lung volumes, diffusing capacity, and static and dynamic compliance. There was no significant difference between MM controls and MZ heterozygotes in the physiologic variables measured.

Physiologic and morphologic observations of the effects of intravenous elastase on the lung.

Intravenous administration of porcine pancreatic elastase to hamsters produced significant loss of elastic recoil at low volumes. Histology and mean linear intercept of the lungs fixed at a pressure of 20 cm H2O and studied for 3 weeks after administration of elastase were normal. Larger doses of elastase caused immediate fatal, hemorrhagic pulmonary edema. These results confirmed previous morphologic observations of the effects of intravenously administered elastase, but demonstrated that the loss of elastic recoil at low lung volumes is not invariably associated with histologic changes or morphologically with loss of elastin fibers. These observations suggest that submicroscopic lesions may be present and may antedate the earliest morphologic evidence of emphysema and aging in the lung.

Serum trypsin inhibitory capacity and pi phenotypes. II. Prevalence of alpha1-antitrypsin deficiency in an allergy population.

A series of 138 patients seen consecutively in an adult allergy clinic were studied to determine serum alpha1-antitrypsin (alpha1-AT) levels and protease inhibitor (Pi) phenotypes. These were compared with a control group of 700 healthy young adult blood donors. Both total serum trypsin inhibitory capacity (STIC) and alpha1-AT levels as determined by immunoelectrophoresis (IEP) were measured. Phenotypes were determined by antigen-antibody-crossed IEP. Alpha1-AT levels in the allergy group were not significantly different from control values. STIC in the allergy group was 1.34 +/- 0.28 mg. trypsin inhibited per ml. serum and in the controls, 1.32 +/- 0.28 mg. IEP values were 205 +/- vs. 200 +/- 36 mg. per dl. Similarly, no increase in Pi phenotypes known to be related to any disease state was observed. Since Pi phenotypes other than the most common MM are rare in Negro populations, phenotype data were corrected to include only Caucasian subjects. In the allergy group adjusted for racial composition we found 2.86% MZ, 5.72% MS; no SZ, SS or ZZ was detected. A comparable control group contained 3.68% MZ, 6.23% MS, 0.71% SZ-SS, but no ZZ Pi phenotype.

Serum trypsin inhibitory capacity and Pi phenotypes. I. Methods and control values.

Serum trypsin inhibitory capacity determinations are of considerable value in detecting genetically determined types of obstructive pulmonary disease and hepatic disease. These determinations must frequently be followed by determination of protease inhibitor (Pi) phenotype in order to confirm the diagnosis. Piphenotyping has been a specialized and time-consuming procedure, and suggested improvements in the methodology and technics may make it more generally applicable as a clinical laboratory procedure. The prevalence of phenotypes other than MM in a group of 700 control sera from blood donors is reported as a baseline to evaluate typically American populations of mixed ethnic and racial characteristics. There are suggestive differences in prevalences of S and Z genes relating to ethnic stock and racial groups. It is important when comparing the prevalences of S and Z genes in diseasedpopulations to use control groups of similar ethnic and racial compositions. Pi phenotyping is a necessary laboratory procedure in the diagnosis of certain forms of genetically determined chronic obstructive pulmonary disease and hepatic disease. The distributions of all serum protease inhibitory capacity values and those for S and Z Pi phenotypes are shown.