The reeent explosive interest in eell adhesion
molecules (CAMs) is a direet eonsequence of the
fundamental roles they are thought to play during
early embryogenesis and tissue formation [1,2].
The most weIl known of them, studied independently
under the names of N-CAM [3]
(neural-CAM), 02 protein [4] and BSP-2 [5], has
been shown to consist in brain of a family of three
glyeoproteins of Mr 180000, 140000 and 120000
[6,7] which are implicated in neurone-neurone
adhesion by a homophilie binding meehanism
[8,9]. While N-CAM was originally considered to
be limited to neurones in adult tissues, ultrastruetural
immunoeytochemical studies have sinee provided
unequivocal evidenee that glial cells, both
astrocytes [6,10] and Schwann cells [11], also express
N-CAM (see also [12,13]). Apart from a very
limited expression by skeletal muscle at the neuromuscular
junetion [14], its expression in the adult
Correspondence address: O.K. Langley, Unite 44 de
I'INSERM, and Centre de Neurochirnie du CNRS, 5 rue
Blaise Pascal, 67084 Strasbourg Cedex, France
has been largely though not exclusively considered
to be limited to nervous tissues. N-CAM has been
found in eertain eells outside the nervous system
(e.g. chromaffin eells in the adrenal medulla [11])
but such eells are derived from the neural crest.
Here we extend our previous observations on endocrine
eells in the adrenal gland and investigate
the possible expression of N-CAM by other endoerine
eells whieh have a non-neural origin. The present
results indieate a mueh wider distribution of
N-CAM in adult tissues than has previously been
supposed. N-CAM is shown by immunoeytoehemistry
to be expressed by several endoerine eells
of non-neural origin. Immunoehemieal data eonfirm
the presenee of N-CAM determinants typical
of brain in endoerine eells although the relative
proportions differ markedly. In addition, in two of
the tissues examined a lower molecular mass NCAM
positive polypeptide was also detected