Microarray analysis of irradiated growth plate zones following laser microdissection shows later importance of differentially expressed genes during radiorecovery.

Purpose: Potential targets for selective radiorecovery modulation were investigated via the identification of late upregulated genes and pathways during growth plate chondrocyte recovery.

Methods And Materials: Three groups of six 5-week-old male Sprague-Dawley rats underwent fractionated irradiation to the right tibiae over 5 days totaling 17.5 Gy and were then killed at 7, 11, and 16 days following the first radiotherapy fraction.

A key role for membrane transporter NKCC1 in mediating chondrocyte volume increase in the mammalian growth plate.

The mechanisms that underlie growth plate chondrocyte volume increase and hence bone lengthening are poorly understood. Many cell types activate the Na-K-Cl cotransporter (NKCC) to bring about volume increase. We hypothesised that NKCC may be responsible for the volume expansion of hypertrophic chondrocytes.

Microarray cluster analysis of irradiated growth plate zones following laser microdissection.

Purpose: Genes and pathways involved in early growth plate chondrocyte recovery after fractionated irradiation were sought as potential targets for selective radiorecovery modulation.

Materials And Methods: Three groups of six 5-week male Sprague-Dawley rats underwent fractionated irradiation to the right tibiae over 5 days, totaling 17.5 Gy, and then were killed at 7, 11, and 16 days after the first radiotherapy fraction.

Histomorphometric evidence of growth plate recovery potential after fractionated radiotherapy: an in vivo model.

This study evaluated the hypothesis that early growth plate radiorecovery is evident by growth rate, histomorphometric and immunohistochemical end points after exposure to clinically relevant fractionated radiation in vivo. Twenty-four weanling 5-week-old male Sprague-Dawley rats were randomized into eight groups. In each animal, the right distal femur and proximal tibia were exposed to five daily fractions of 3.

Microarray analysis of perichondral and reserve growth plate zones identifies differential gene expressions and signal pathways.

In the growth plate, the reserve and perichondral zones have been hypothesized to have similar functions, but their exact functions are poorly understood. Our hypothesis was that significant differential gene expression exists between perichondral and reserve chondrocytes that may differentiate the respective functions of these two zones. Normal Sprague-Dawley rat growth plate chondrocytes from the perichondral zone (PC) and reserve zone (RZ) were isolated by laser microdissection and then subjected to microarray analysis.

Connective tissue growth factor and insulin-like growth factor 2 show upregulation in early growth plate radiorecovery response following irradiation.

Introduction: The growth plate response following radiotherapy is poorly understood. In particular, little is known about the changes in growth plate growth factors and cytokines following irradiation. The hypothesis was that a limited number of growth factors and cytokines play a role in growth plate proliferative and hypertrophic chondrocyte radio-recovery.