Studies on the Hexapod Nervous System. Iv. A Cytological and Cytochemical Study of Neurons and Their Inclusions in the Brain of a Cockroach Periplaneta Americana (L.)

Studies on the neursecretory system of the female mole cricket Gryllotalpa africana (Orthoptera: Gryllotalpidae)

“…In the closely related species S. gregaria four, A, B, C and D, types of cells have been described, but only A-and B-cells have been regarded as neurosecretory cells (Highnarn, 1961). The A-cells of G. africana correspond with the A-cells of S. gregaria and P. umericana described by Highnam (1961) and Pipa (1961).…”

“…In insects, Sloper (1957) was the first to demonstrate with performic acid-alcian blue (PAAB) method of Adams & Sloper (1956) the presence of a substance rich in proteinbound cystine and/or cysteine in the neurosecretory system of Leucophaea maderae. Since then, with the same technique cystine rich NSM has been demonstrated in the neurosecretory system of P. aniericana by Pipa (1961) and in Adelphocoris lineolatus by Ewen (1962). The modified technique namely PAVB (performic acid-victoria blue) method of Humberstone (see Dogra & Tandan, 1964) has also demonstrated cystine rich material in the neurosecretory system of G. africana.…”

“…In order to reveal the third centre, namely the ncurosecretory pathway, which lies deeply, routine sectioning technique is preferred since such a procedure facilitates the action of weak oxidant. 0 1 1 the basis of the difference in the staining reaction Nayar (1955) classified the neurosecretory cells of the pars intercerebralis into A-cells and B-cells and subsequently this classification \\as followed by other workers using karious techniques (KBpf, 1957, Johansson, 1958Pipa. 1961;McLeod & Beck, 1963).…”

An in situ study of cystine and cysteine‐rich neurosecretory cells in the brain of Sarcophaga ruficornis (Fabricius, 1794) (Diptera, Cyclorrhapha)

“…The inclusions of a smaller number of AF (or PF) -positive neurones in the pars intercerebralis of Periplaneta americana (L.) also react positively to the histo-and cyto-chemical PAAB technique of Adams & Sloper (1956) and the alkaline tetrazolium reaction of Barnett & Seligman (1954) (Pipa 1961(Pipa , 1962. Pipa (1961) called the PFand AB-positive inclusions "A-cell NSM" and the neurones the A-cells, the elaborated inclusions of the majority of neurones, PF-positive but AB-negative, being called "beta-granules". In S. ruficornis, the number of neurones (or A-cells) that elaborate PF-and VB-positive inclusions (or the A-cell NSM) is determinable directly, and those neurones that elaborate PF-positive and VB-negative inclusions (beta-granules) can be ascertained indirectly.…”

“…From the foregoing, it emerges that VB-negative neurones cbntain PF-positive perikaryal inclusions throughout the metamorphic phase, although the number of such neurones varies, whereas the VB-positive neurones do not contain PF (or even VB)-positive inclusions throughout the metamorphic phase. Consequently, the VB-negative neurones, which elaborate beta-granules, are active throughout postembryonic development in contrast to the VB-positive ones, which elaborate the neurosecretory material of the A-cell (NSM) (Pipa, 1961).…”