Changes in skull components of the squirrel monkey evoked by growth and nutrition: An experimental study

Abstract

Twenty weanling 6-month-old male squirrel monkeys were allotted to the following treatments: 1) first control animals were killed at weaning; 2) second control animals were killed when 24 months old; and 3) malnourished animals were fed on a low-protein diet and killed at age 24 months. Lateral and vertical teleradiographies were taken. Growth of the neurocranial and splanchnocranial components were measured by volumetric (size estimators) and morphometric (shape estimators) indices. All facial components grew. The neurocranial components showed a heterogeneous behavior: The anteroneural component remained stable, and the increase of the midneural component was compensated by a decrease in the posteroneural component. Malnutrition affected the growths of 1) the craniofacial complex, 2) the splanchnocranium, and 3) the respiratory and midneural components. Growth influenced skull shape through 1) increases of the splanchnocranium and the midneural component relative to the neurocranium; 2) decreases of the masticatory and optic components relative to the splanchnocranium, and 3) decreases of the anteroneural and posteroneural components relative to the neurocranium. Malnutrition influenced skull shape through the relationship between the anteroneural component and the neurocranium. These results confirmed the existence of functional interrelationships among the cranial components. A new approach to craniological studies is suggested.

Morphometric and ultrastructural analysis of different pituitary cell populations in undernourished monkeys

“…It is known that in squirrel monkeys undernutrition caused by a low-protein diet produces a decrease in body and skull size, but not in brain weight, which was supported by the craniofacial morphometric patterns previously described by our group (1,21).…”

“…In platyrrhine monkeys, undernutrition alters the growth of the neurocranial and facial functional components (1,2). The areas of higher growth (nasal bones, parietal and basioccipital bones, occipital squama, and palatomaxillary procidentia) are especially affected by undernutrition, suffering alteration in size, though not in shape (2,3), and sexual dimorphic inversion.…”

The experimental method in Biological Anthropology. History and current status in Argentina

“…Los objetivos de los trabajos fueron coincidentes con los anteriormente realizados en ratas, respecto a la influencia de la desnutrición sobre la morfología craneofacial (Dressino, 1991;Dressino y Pucciarelli, 1996, 1997Pucciarelli et al, 1990Pucciarelli et al, , 2000 y sobre los cambios ultraestructurales e inmunohistoquímicos de diferentes poblaciones de células pituitarias (Cónsole et al, 2001a, b).…”

Effect of Undernutrition on Cranial Components and Somatotroph-Lactotroph Pituitary Populations in the Squirrel Monkey <i>(Saimiri sciureus boliviensis)</i>

“…The length (Lx) and the height (Hx) from the first, as well as the width (Wx) from the second, were measured for each cranial component. Then, the volumetric and the morphometric indices were calculated according to formulas previously developed [Pucciarelli et al, 1990]. The following differences in size were estimated by the volumetric indices: anteroneural (ANVI), midneural (MNVI), posteroneural (PNVI), optic (OPVI), respiratory (REVI) and masticatory (MAVI) for the minor components, and neurocranial (NEVI) and facial (FAVI) for the major ones.…”

“…Experimental animal models of undernutrition on the basis of the administration of a low-protein diet have allowed an extensive morphometric study by measuring neurocranial and facial functional components [Pucciarelli et al, 1990;Oyhenart and Pucciarelli, 1992;Pucciarelli and Dressino, 1996].…”