The effect of tetracyclines on quantitative measures of osteoclast morphology

• Published in: Bioscience reports Vol. 13; no. 3; p. 175
• Main Authors: Zaidi, M, Moonga, B S, Huang, C L, Towhidul Alam, A S, Shankar, V S, Pazianas, M, Eastwood, J B, Datta, H K, Rifkin, B R
• Format: Journal Article
• Language: English
• Published: England 01.06.1993
• Subjects: Animals; Calcium - analysis; Calcium - metabolism; Calcium - physiology; Image Processing, Computer-Assisted; Linear Models; Microscopy, Phase-Contrast; Minocycline - pharmacology; Osteoclasts - chemistry; Osteoclasts - cytology; Osteoclasts - physiology; Rats; Rats, Wistar; Receptors, Cytoplasmic and Nuclear - analysis; Receptors, Cytoplasmic and Nuclear - metabolism; Receptors, Cytoplasmic and Nuclear - physiology; Tetracycline - pharmacology
• ISSN: 0144-8463
• DOI: 10.1007/BF01149962

We report the effects of the tetracycline analogues 4-dedimethylaminotetracycline (CMT-1) and minocycline on osteoclast spreading and motility. Both agents influenced the morphometric descriptor of cell spread area, rho, producing cellular retraction or an R effect (half-times: 30 and 44 minutes for CMT-1 and minocycline, respectively). At the concentrations employed, the tetracycline-induced R effects were significantly slower than, but were qualitatively similar to, those resulting from Ca2+ "receptor" activation through the application of 15 mM-[Ca2+] (slopes: -1.25, -0.18, and -4.40/minute for 10 mg/l-[CMT-1], 10 mg/l-[minocycline] and 15 mM-[Ca2+], respectively). In contrast, the same tetracycline concentrations did not influence osteoclast margin ruffling activity as described by mu, a motility descriptor known to be influenced by elevations of cellular cyclic AMP. Thus, the tetracyclines exert morphometric effects comparable to changes selectively activated by occupancy of the osteoclast Ca2+ "receptor" which may act through an increase in cytosolic [Ca2+].