1 Ghrelin is a fast-acting hormone that plays a vital role in meal initiation and contributes to weight gain. 2  Leptin mediates long-term regulation of energy balance and suppresses food intake, thereby inducing weight loss.  Both hormones can be controlled naturally, primarily though exercise and stress management.
Surgical retractors. A retractor is a surgical instrument with which a surgeon can either actively separate the edges of a surgical incision or wound, or can hold back underlying organs and tissues, so that body parts under the incision may be accessed. The two are each available in many shapes, sizes, and styles.
a rib whose distal extremity is unattached to an adjacent rib or the sternum. rib retractor. heavy duty surgical instrument for separating ribs to allow surgeon better access to thoracic contents. See finochietto rib spreader.ib. any of the paired bones, 12 on either side, extending from the thoracic vertebrae toward the median line on the ventral aspect of the trunk, forming the major part of the thoracic skeleton. Called also costa. See anatomic Table of Bones in the Appendices.