var receiverEmailAddress = '{宛先アドレス}@*****.com'
var senderEmailAddress = '{作成したGメール}@gmail.com'
var senderEmailPassword = '{作成したGメールアカウントのパスワード}'

var nodemailer = require('nodemailer');
var transporter = nodemailer.createTransport({
  host: 'smtp.gmail.com',
  port: 465,
  secure: true, // SSL
  auth: {
    user: senderEmailAddress,
    pass: senderEmailPassword
  }
});
var mailOptions1 = {
  from: senderEmailAddress,
  to: receiverEmailAddress,
  subject: '{件名}',
  text: '{本文}'
};
transporter.sendMail(mailOptions1, function (error, info) {
  if (error) {
    console.log(error);
  } else {
    console.log('Email sent: ' + info.response);
  }
});