Quantification of human plasma inorganic pyrophosphate
โ Scribed by Lawrence M. Ryan; Franklin Kozin; Daniel J. Mccarty
- Publisher
- John Wiley and Sons
- Year
- 1979
- Tongue
- English
- Weight
- 309 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0004-3591
No coin nor oath required. For personal study only.
โฆ Synopsis
Abstract
Plasma inorganic pyrophosphate (PPi) levels rose predictably (28%) after vigorous systemic exercise and returned to baseline values after 30 minutes of rest. Plasma PPi levels were greater (36%) in femoral venous blood than in femoral arterial blood. Forearm muscular exercise, however, did not result in a detectable rise in plasma PPi levels in antecubital veins. The physiologic reasons for both the systemic exercise effect and the arteriovenous differences remain unknown. Measurement of plasma PPi for 10 consecutive days in a single normal subject under basal conditions, where these and other previously identified biologic variables (fasting and diurnal variation) were controlled, showed a coefficient of variation of 12.7%. Thus biologic variability contributed less to observed variation in plasma PPi than did methodologic errors (coefficient of variation of method = 8%). The striking reproducibility of plasma PPi in this subject suggests that this important metabolite is under rather tight homeostatic control.
๐ SIMILAR VOLUMES
Chondrocytes in vivo show distinct characteristics related to their structure and function. These in- clude an extracellular accumulation of proteoglycans and a specific type of collagen characteristic of articular cartilage, designated as [c~,(11)]~. These substances constitute the major macromolec
Objective. To investigate cellular signaling mechanisms that influence chondrocyte production of inorganic pyrophosphate (PPi), which promotes calcium pyrophosphate dihydrate (CPPD) crystal deposition. Methods. Articular chondrocyte and cartilage cultures were stimulated with protein kinase C (PKC)